diff --git a/source/src/audiomanager.cpp b/source/src/audiomanager.cpp
index 7fe21a14..8b46eb00 100644
--- a/source/src/audiomanager.cpp
+++ b/source/src/audiomanager.cpp
@@ -233,20 +233,23 @@ int audiomanager::addsound(char *name, int vol, int maxuses, bool loop, vector<s
     return sounds.length()-1;
 }
 
-void audiomanager::preloadmapsound(entity &e, bool trydl)
+bool audiomanager::preloadmapsound(entity &e, bool trydl)
 {
-    if(e.type!=SOUND || !mapsounds.inrange(e.attr1)) return;
+    if(e.type!=SOUND || !mapsounds.inrange(e.attr1)) return false;
     sbuffer *buf = mapsounds[e.attr1].buf;
-    if(!buf->load(trydl) && !trydl) conoutf("\f3failed to load sample %s", buf->name);
+    if(!buf->load(trydl) && !trydl) { conoutf("\f3failed to load sample %s", buf->name); return false; }
+    return true;
 }
 
-void audiomanager::preloadmapsounds(bool trydl)
+bool audiomanager::preloadmapsounds(bool trydl)
 {
+    int missing = 0;
     loopv(ents)
     {
         entity &e = ents[i];
-        if(e.type==SOUND) preloadmapsound(e, trydl);
+        if(e.type == SOUND && !preloadmapsound(e, trydl)) missing++;
     }
+    return !missing;
 }
 
 void audiomanager::applymapsoundchanges() // during map editing, drop all mapsounds so they can be re-added
@@ -820,7 +823,11 @@ COMMANDF(mapsound, "si", (char *name, int *maxuses)
     filtertext(name, name, FTXT__MEDIAFILEPATH);
     defformatstring(stripped)("%s%s", mapsoundbasepath, name);
     unixpath(path(stripped));
-    if(mapconfigdata.mapsoundlines.length() > 254) conoutf("\f3error: too many mapsounds");
+    if(mapconfigdata.mapsoundlines.length() > 254)
+    {
+        conoutf("\f3error: too many mapsounds");
+        flagmapconfigerror(LWW_CONFIGERR);
+    }
     else if(!strncmp(stripped, mapsoundbasepath, mapsoundbasepath_n))
     {
         name = stripped + mapsoundbasepath_n;
@@ -832,7 +839,11 @@ COMMANDF(mapsound, "si", (char *name, int *maxuses)
         mapsoundchanged = 1;
         flagmapconfigchange();
     }
-    else conoutf("\f3error: mapsound \"%s\" outside packages/audio/", stripped);
+    else
+    {
+        conoutf("\f3error: mapsound \"%s\" outside packages/audio/", stripped);
+        flagmapconfigerror(LWW_CONFIGERR);
+    }
 });
 
 COMMANDF(registermusic, "s", (char *name)
diff --git a/source/src/clients2c.cpp b/source/src/clients2c.cpp
index 3f40db1d..ee5bad28 100644
--- a/source/src/clients2c.cpp
+++ b/source/src/clients2c.cpp
@@ -37,11 +37,11 @@ bool changemapserv(char *name, int mode, int download, int revision)        // f
     if(m_demo) return true;
     if(m_coop)
     {
-        if(!name[0] || !load_world(name)) empty_world(0, true);
+        if(!name[0] || load_world(name) < 0) empty_world(0, true);
         return true;
     }
     else if(player1->state==CS_EDITING) { /*conoutf("SANITY drop from EDITING");*/ toggleedit(true); } // fix stuck-in-editmode bug
-    bool loaded = load_world(name);
+    bool loaded = load_world(name) >= 0;
     if(download > 0)
     {
         bool revmatch = hdr.maprevision == revision || revision == 0;
diff --git a/source/src/command.cpp b/source/src/command.cpp
index 3c8f17cc..d48da5f4 100644
--- a/source/src/command.cpp
+++ b/source/src/command.cpp
@@ -691,6 +691,7 @@ char *executeret(const char *p)                            // all evaluation hap
                             {
                                 i1 = i1<id->minval ? id->minval : id->maxval;       // clamp to valid range
                                 conoutf("valid range for %s is %d..%d", id->name, id->minval, id->maxval);
+                                flagmapconfigerror(LWW_SCRIPTERR);
                             }
                             *id->storage.i = i1;
                             if(id->fun) ((void (__cdecl *)())id->fun)();            // call trigger function if available
@@ -707,7 +708,7 @@ char *executeret(const char *p)                            // all evaluation hap
                             {
                                 f1 = f1<id->minvalf ? id->minvalf : id->maxvalf;       // clamp to valid range
                                 conoutf("valid range for %s is %s..%s", id->name, floatstr(id->minvalf), floatstr(id->maxvalf));
-                                //scripterr(); // Why throw this error here when it's not done for ID_VAR above? Only difference is datatype, both are "valid range errors". // Bukz 2011june04
+                                flagmapconfigerror(LWW_SCRIPTERR * 2);
                             }
                             *id->storage.f = f1;
                             if(id->fun) ((void (__cdecl *)())id->fun)();            // call trigger function if available
@@ -1023,6 +1024,7 @@ void scripterr()
 {
     if(curcontext) conoutf("(%s: %s)", curcontext, curinfo);
     else conoutf("(from console or builtin)");
+    flagmapconfigerror(LWW_SCRIPTERR * 4);
 }
 
 void setcontext(const char *context, const char *info)
diff --git a/source/src/md2.h b/source/src/md2.h
index b8d2303d..52619301 100644
--- a/source/src/md2.h
+++ b/source/src/md2.h
@@ -257,7 +257,7 @@ struct md2 : vertmodel
         Texture *skin;
         loadskin(loadname, pname, skin);
         loopv(mdl.meshes) mdl.meshes[i]->skin  = skin;
-        if(skin==notexture) conoutf("could not load model skin for %s", name1);
+        if(skin==notexture) { conoutf("could not load model skin for %s", name1); flagmapconfigerror(LWW_MODELERR); }
         loadingmd2 = this;
         defformatstring(name2)("packages/models/%s/md2.cfg", loadname);
         per_idents = false;
@@ -280,15 +280,15 @@ struct md2 : vertmodel
 
 void md2anim(char *anim, int *frame, int *range, float *speed)
 {
-    if(!loadingmd2 || loadingmd2->parts.empty()) { conoutf("not loading an md2"); return; }
+    if(!loadingmd2 || loadingmd2->parts.empty()) { conoutf("not loading an md2"); flagmapconfigerror(LWW_MODELERR); return; }
     int num = findanim(anim);
-    if(num<0) { conoutf("could not find animation %s", anim); return; }
+    if(num<0) { conoutf("could not find animation %s", anim); flagmapconfigerror(LWW_MODELERR); return; }
     loadingmd2->parts.last()->setanim(num, *frame, *range, *speed);
 }
 
 void md2tag(char *name, char *vert1, char *vert2, char *vert3, char *vert4)
 {
-    if(!loadingmd2 || loadingmd2->parts.empty()) { conoutf("not loading an md2"); return; }
+    if(!loadingmd2 || loadingmd2->parts.empty()) { conoutf("not loading an md2"); flagmapconfigerror(LWW_MODELERR); return; }
     md2::part &mdl = *loadingmd2->parts.last();
     int indexes[4] = { -1, -1, -1, -1 }, numverts = 0;
     loopi(4)
@@ -319,17 +319,17 @@ void md2tag(char *name, char *vert1, char *vert2, char *vert3, char *vert4)
             }
             if(!mdl.meshes.empty()) indexes[i] = mdl.meshes[0]->findvert(axis, dir);
         }
-        if(indexes[i] < 0) { conoutf("could not find vertex %s", vert); return; }
+        if(indexes[i] < 0) { conoutf("could not find vertex %s", vert); flagmapconfigerror(LWW_MODELERR); return; }
         numverts = i + 1;
     }
-    if(!mdl.gentag(name, indexes, numverts)) { conoutf("could not generate tag %s", name); return; }
+    if(!mdl.gentag(name, indexes, numverts)) { conoutf("could not generate tag %s", name); flagmapconfigerror(LWW_MODELERR); return; }
 }
 
 void md2emit(char *tag, int *type, int *arg1, int *arg2)
 {
-    if(!loadingmd2 || loadingmd2->parts.empty()) { conoutf("not loading an md2"); return; };
+    if(!loadingmd2 || loadingmd2->parts.empty()) { conoutf("not loading an md2"); flagmapconfigerror(LWW_MODELERR); return; };
     md2::part &mdl = *loadingmd2->parts.last();
-    if(!mdl.addemitter(tag, *type, *arg1, *arg2)) { conoutf("could not find tag %s", tag); return; }
+    if(!mdl.addemitter(tag, *type, *arg1, *arg2)) { conoutf("could not find tag %s", tag); flagmapconfigerror(LWW_MODELERR); return; }
 }
 
 COMMAND(md2anim, "siif");
diff --git a/source/src/md3.h b/source/src/md3.h
index d1f4c597..bf5cdcca 100644
--- a/source/src/md3.h
+++ b/source/src/md3.h
@@ -63,6 +63,7 @@ struct md3 : vertmodel
             {
                 delete f;
                 conoutf("md3: corrupted header");
+                flagmapconfigerror(LWW_MODELERR);
                 return false;
             }
 
@@ -244,7 +245,7 @@ struct md3 : vertmodel
             Texture *skin;
             loadskin(loadname, pname, skin);
             loopv(mdl.meshes) mdl.meshes[i]->skin  = skin;
-            if(skin==notexture) conoutf("could not load model skin for %s", name1);
+            if(skin==notexture) { conoutf("could not load model skin for %s", name1); flagmapconfigerror(LWW_MODELERR); }
         }
         loopv(parts) parts[i]->scaleverts(scale/16.0f, vec(translate.x, -translate.y, translate.z));
         radius = calcradius(zradius);
@@ -256,20 +257,20 @@ struct md3 : vertmodel
 
 void md3load(char *model)
 {
-    if(!loadingmd3) { conoutf("not loading an md3"); return; };
+    if(!loadingmd3) { conoutf("not loading an md3"); flagmapconfigerror(LWW_MODELERR); return; };
     filtertext(model, model, FTXT__MEDIAFILEPATH);
     defformatstring(filename)("%s/%s", md3dir, model);
     md3::md3part &mdl = *new md3::md3part;
     loadingmd3->parts.add(&mdl);
     mdl.model = loadingmd3;
     mdl.index = loadingmd3->parts.length()-1;
-    if(!mdl.load(path(filename))) conoutf("could not load %s", filename); // ignore failure
+    if(!mdl.load(path(filename))) { conoutf("could not load %s", filename); flagmapconfigerror(LWW_MODELERR); } // ignore failure
 }
 
 void md3skin(char *objname, char *skin)
 {
     filtertext(skin, skin, FTXT__MEDIAFILEPATH);
-    if(!loadingmd3 || loadingmd3->parts.empty()) { conoutf("not loading an md3"); return; };
+    if(!loadingmd3 || loadingmd3->parts.empty()) { conoutf("not loading an md3"); flagmapconfigerror(LWW_MODELERR); return; };
     md3::part &mdl = *loadingmd3->parts.last();
     bool used = false;
     loopv(mdl.meshes)
@@ -287,29 +288,30 @@ void md3skin(char *objname, char *skin)
         defformatstring(s)(", possibilities are: *");
         loopv(mdl.meshes) concatformatstring(s, "|%s", mdl.meshes[i]->name);
         conoutf("mesh \"%s\" not found in model %s, skin %s not loaded%s", objname, loadingmd3->loadname, skin, mdl.meshes.length() ? s : "");
+        flagmapconfigerror(LWW_MODELERR);
     }
 }
 
 void md3anim(char *anim, int *startframe, int *range, float *speed)
 {
-    if(!loadingmd3 || loadingmd3->parts.empty()) { conoutf("not loading an md3"); return; };
+    if(!loadingmd3 || loadingmd3->parts.empty()) { conoutf("not loading an md3"); flagmapconfigerror(LWW_MODELERR); return; };
     int num = findanim(anim);
-    if(num<0) { conoutf("could not find animation %s", anim); return; };
+    if(num<0) { conoutf("could not find animation %s", anim); flagmapconfigerror(LWW_MODELERR); return; };
     loadingmd3->parts.last()->setanim(num, *startframe, *range, *speed);
 }
 
 void md3link(int *parent, int *child, char *tagname)
 {
     if(!loadingmd3) { conoutf("not loading an md3"); return; };
-    if(!loadingmd3->parts.inrange(*parent) || !loadingmd3->parts.inrange(*child)) { conoutf("no models loaded to link"); return; }
-    if(!loadingmd3->parts[*parent]->link(loadingmd3->parts[*child], tagname)) conoutf("could not link model %s", loadingmd3->loadname);
+    if(!loadingmd3->parts.inrange(*parent) || !loadingmd3->parts.inrange(*child)) { conoutf("no models loaded to link"); flagmapconfigerror(LWW_MODELERR); return; }
+    if(!loadingmd3->parts[*parent]->link(loadingmd3->parts[*child], tagname)) { conoutf("could not link model %s", loadingmd3->loadname); flagmapconfigerror(LWW_MODELERR); }
 }
 
 void md3emit(char *tag, int *type, int *arg1, int *arg2)
 {
-    if(!loadingmd3 || loadingmd3->parts.empty()) { conoutf("not loading an md3"); return; };
+    if(!loadingmd3 || loadingmd3->parts.empty()) { conoutf("not loading an md3"); flagmapconfigerror(LWW_MODELERR); return; };
     md3::part &mdl = *loadingmd3->parts.last();
-    if(!mdl.addemitter(tag, *type, *arg1, *arg2)) { conoutf("could not find tag %s", tag); return; }
+    if(!mdl.addemitter(tag, *type, *arg1, *arg2)) { conoutf("could not find tag %s", tag); flagmapconfigerror(LWW_MODELERR); return; }
 }
 
 COMMAND(md3load, "s");
diff --git a/source/src/protos.h b/source/src/protos.h
index 364940af..b14edb4d 100644
--- a/source/src/protos.h
+++ b/source/src/protos.h
@@ -429,7 +429,7 @@ extern const char *gettextureslot(int i);
 extern bool reloadtexture(Texture &t);
 extern void reloadtextures();
 extern void blitsurface(SDL_Surface *dst, SDL_Surface *src, int x, int y);
-extern void loadskymap(bool reload);
+extern bool loadskymap(bool reload);
 extern void *texconfig_copy();
 extern void texconfig_delete(void *s);
 extern uchar *texconfig_paste(void *_s, uchar *usedslots);
@@ -813,18 +813,20 @@ extern bool addscorchmark(vec &o, float radius = 7);
 extern void render_particles(int time, int typemask = ~0);
 
 // worldio
+enum { LWW_ENTATTROVERFLOW = 0x1, LWW_DECODEERR = 0x10, LWW_WORLDERROR = 0x100, LWW_MISSINGMEDIA = 0x1000, LWW_CONFIGERR = 0x10000, LWW_MODELERR = 0x100000, LWW_SCRIPTERR = 0x1000000 };
 extern const char *setnames(const char *name);
 extern void save_world(char *mname, bool skipoptimise = false, bool addcomfort = false);
-extern bool load_world(char *mname);
+extern int load_world(char *mname);
 extern void writemap(char *name, int size, uchar *data);
 extern void writecfggz(char *name, int size, int sizegz, uchar *data);
 extern uchar *readmap(char *name, int *size, int *revision);
 extern uchar *readmcfggz(char *name, int *size, int *sizegz);
 extern void rlencodecubes(vector<uchar> &f, sqr *s, int len, bool preservesolids);
-extern void rldecodecubes(ucharbuf &f, sqr *s, int len, int version, bool silent);
+extern bool rldecodecubes(ucharbuf &f, sqr *s, int len, int version, bool silent);
 extern void clearheaderextras();
 extern void automapconfig();
 extern void flagmapconfigchange();
+extern void flagmapconfigerror(int what);
 extern void getcurrentmapconfig(vector<char> &f, bool onlysounds);
 extern char *mapinfo_license, *mapinfo_comment;
 extern void setmapinfo(const char *newlicense = NULL, const char *newcomment = NULL);
@@ -879,7 +881,7 @@ extern void resetmdlnotfound();
 extern void preload_playermodels();
 extern void preload_entmodels();
 extern void preload_hudguns();
-extern void preload_mapmodels(bool trydl = false);
+extern bool preload_mapmodels(bool trydl = false);
 extern void renderclients();
 extern void renderclient(playerent *d);
 extern void renderclient(playerent *d, const char *mdlname, const char *vwepname, int tex = 0);
diff --git a/source/src/rendermodel.cpp b/source/src/rendermodel.cpp
index 9501777f..1ff253c5 100644
--- a/source/src/rendermodel.cpp
+++ b/source/src/rendermodel.cpp
@@ -11,7 +11,7 @@ mapmodelattributes loadingattributes;
 #include "md2.h"
 #include "md3.h"
 
-#define checkmdl if(!loadingmodel) { conoutf("not loading a model"); return; }
+#define checkmdl if(!loadingmodel) { conoutf("not loading a model"); flagmapconfigerror(LWW_MODELERR); return; }
 
 void mdlcullface(int *cullface)
 {
@@ -119,7 +119,11 @@ void mapmodel(int *rad, int *h, int *zoff, char *scale, char *name)
         mmi.h = *h;
         mmi.zoff = *zoff;
         mmi.scale = atof(scale);
-        if(mmi.scale < 0.25f || mmi.scale > 4.0f) mmi.scale = 1.0f;
+        if(mmi.scale < 0.25f || mmi.scale > 4.0f)
+        {
+            mmi.scale = 1.0f;
+            if(strcmp(scale, "0")) flagmapconfigerror(LWW_CONFIGERR * 2);
+        }
         mmi.m = NULL;
 
         filtertext(name, name, FTXT__MEDIAFILEPATH);
@@ -382,7 +386,11 @@ model *loadmodel(const char *name, int i, bool trydl)     // load model by name
         {
             mdllookup.access(m->name(), m);
             setmodelattributes(m->name(), loadingattributes);
-            if(m->shadowdist && !m->cullface) conoutf("\f3mapmodel config error: disabling face culling in combination with shadows will cause visual errors (%s)", m->name());
+            if(m->shadowdist && !m->cullface)
+            {
+                conoutf("\f3mapmodel config error: disabling face culling in combination with shadows will cause visual errors (%s)", m->name());
+                flagmapconfigerror(LWW_MODELERR);
+            }
         }
         loadingmodel = NULL;
     }
@@ -896,15 +904,17 @@ void preload_entmodels()
      }
 }
 
-void preload_mapmodels(bool trydl)
+bool preload_mapmodels(bool trydl)
 {
+    int missing = 0;
     loopv(ents)
     {
         entity &e = ents[i];
         if(e.type!=MAPMODEL || !mapmodels.inrange(e.attr2)) continue;
-        loadmodel(NULL, e.attr2, trydl);
-        if(e.attr4) lookuptexture(e.attr4, notexture, trydl);
+        if(!loadmodel(NULL, e.attr2, trydl)) missing++;
+        if(e.attr4 && lookuptexture(e.attr4, notexture, trydl) == notexture) missing++;
     }
+    return !missing;
 }
 
 inline void renderhboxpart(playerent *d, vec top, vec bottom, vec up)
diff --git a/source/src/sound.h b/source/src/sound.h
index b0dc8fff..1d7e2511 100644
--- a/source/src/sound.h
+++ b/source/src/sound.h
@@ -390,8 +390,8 @@ public:
 
     // init & setup
     void initsound();
-    void preloadmapsound(entity &e, bool trydl = false);
-    void preloadmapsounds(bool trydl = false);
+    bool preloadmapsound(entity &e, bool trydl = false);
+    bool preloadmapsounds(bool trydl = false);
     void applymapsoundchanges();
 
     // configuration
diff --git a/source/src/texture.cpp b/source/src/texture.cpp
index 527275ef..f80554aa 100644
--- a/source/src/texture.cpp
+++ b/source/src/texture.cpp
@@ -501,7 +501,11 @@ COMMANDF(texture, "fs", (float *scale, char *name)
     intret(slots.length());
     Slot &s = slots.add();
     _texture(s, scale, name);
-    if(*scale < 0.0f || *scale > 4.0f) conoutf("\f3texture slot #%d \"%s\" error: scale factor %.7g out of range 0..4", slots.length() - 1, name, *scale);
+    if(*scale < 0.0f || *scale > 4.0f)
+    {
+        conoutf("\f3texture slot #%d \"%s\" error: scale factor %.7g out of range 0..4", slots.length() - 1, name, *scale);
+        flagmapconfigerror(LWW_CONFIGERR * 4);
+    }
     flagmapconfigchange();
 });
 
@@ -566,7 +570,7 @@ Texture *sky[6] = {NULL, NULL, NULL, NULL, NULL, NULL};
 
 SVARF(loadsky, "", { loadskymap(false); });
 
-void loadskymap(bool reload)
+bool loadskymap(bool reload)
 {
     const char *side[] = { "lf", "rt", "ft", "bk", "dn", "up" };
     const char *legacyprefix = "textures/skymaps/";
@@ -582,7 +586,7 @@ void loadskymap(bool reload)
         }
         flagmapconfigchange();
     }
-    bool old_silent_texture_load = silent_texture_load;
+    bool old_silent_texture_load = silent_texture_load, success = true;
     if(autodownload && execcontext == IEXC_MAPCFG) silent_texture_load = true;
     loopi(6)
     {
@@ -593,8 +597,10 @@ void loadskymap(bool reload)
             requirepackage(PCK_SKYBOX, loadsky);
             break;
         }
+        if(sky[i] == notexture && reload) success = false;
     }
     silent_texture_load = old_silent_texture_load;
+    return success;
 }
 
 void loadnotexture(char *c)
@@ -606,7 +612,7 @@ void loadnotexture(char *c)
         filtertext(mapconfigdata.notexturename, c, FTXT__MEDIAFILEPATH);
         defformatstring(p)("packages/textures/%s", mapconfigdata.notexturename);
         noworldtexture = textureload(p);
-        if(noworldtexture==notexture) conoutf("could not load alternative texture '%s'.", p);
+        if(noworldtexture==notexture) { conoutf("could not load alternative texture '%s'.", p); flagmapconfigerror(LWW_CONFIGERR * 8); }
     }
     flagmapconfigchange();
 }
diff --git a/source/src/worldio.cpp b/source/src/worldio.cpp
index fb0a66b9..ab9cdecc 100644
--- a/source/src/worldio.cpp
+++ b/source/src/worldio.cpp
@@ -168,7 +168,7 @@ void rlencodecubes(vector<uchar> &f, sqr *s, int len, bool preservesolids) // ru
     spurge;
 }
 
-void rldecodecubes(ucharbuf &f, sqr *s, int len, int version, bool silent) // run-length decoding of a series of cubes (version is only relevant, if < 6)
+bool rldecodecubes(ucharbuf &f, sqr *s, int len, int version, bool silent) // run-length decoding of a series of cubes (version is only relevant, if < 6)
 {
     sqr *t = NULL, *e = s + len;
     while(s < e)
@@ -215,7 +215,7 @@ void rldecodecubes(ucharbuf &f, sqr *s, int len, int version, bool silent) // ru
                 if(type<0 || type>=MAXTYPE)
                 {
                     if(!silent) conoutf("while reading map at %d: type %d out of range", int(cubicsize - (e - s)), type);
-                    f.overread();
+                    f.forceoverread();
                     continue;
                 }
                 sqrdefault(s);
@@ -236,6 +236,7 @@ void rldecodecubes(ucharbuf &f, sqr *s, int len, int version, bool silent) // ru
         t = s;
         s++;
     }
+    return !f.overread();  // true: no problem
 }
 
 // headerextra stores additional data in a map file (support since format 10)
@@ -282,7 +283,7 @@ void unpackheaderextra(uchar *buf, int len)  // break the extra data from the ma
     {
         int len = getuint(p), flags = getuint(p), type = flags & HX_TYPEMASK;
         if(p.overread() || len > p.remaining()) break;
-        clientlogf(" found headerextra \"%s\", %d bytes%s", hx_name(type), len, flags & HX_FLAG_PERSIST ? "persistent" : "");  // debug info
+        clientlogf(" found headerextra \"%s\", %d bytes%s", hx_name(type), len, flags & HX_FLAG_PERSIST ? ", persistent" : "");  // debug info
         headerextras.add(new headerextra(len, flags, p.subbuf(len).buf));
     }
 }
@@ -414,6 +415,13 @@ void flagmapconfigchange()
     if(execcontext != IEXC_MAPCFG && hdr.flags & MHF_AUTOMAPCONFIG) unsavededits++;
 }
 
+int mapconfigerror = 0;
+
+void flagmapconfigerror(int what)
+{
+    if(execcontext == IEXC_MAPCFG || execcontext == IEXC_MDLCFG) mapconfigerror |= what;
+}
+
 void getcurrentmapconfig(vector<char> &f, bool onlysounds)
 {
     if(!onlysounds)
@@ -757,7 +765,7 @@ extern float Mh;
 
 static string lastloadedconfigfile;
 
-bool load_world(char *mname)        // still supports all map formats that have existed since the earliest cube betas!
+int load_world(char *mname)        // still supports all map formats that have existed since the earliest cube betas!
 {
     const int sizeof_header = sizeof(header), sizeof_baseheader = sizeof_header - sizeof(int) * 16;
     stopwatch watch;
@@ -775,23 +783,23 @@ bool load_world(char *mname)        // still supports all map formats that have
     if(!validmapname(mname))
     {
         conoutf("\f3Invalid map name. It must only contain letters, digits, '-', '_' and be less than %d characters long", MAXMAPNAMELEN);
-        return false;
+        return -1;
     }
     stream *f = opengzfile(cgzname, "rb");
-    if(!f) { conoutf("\f3could not read map %s", cgzname); return false; }
+    if(!f) { conoutf("\f3could not read map %s", cgzname); return -2; }
     if(unsavededits) xmapbackup("load_map_", mname);
     unsavededits = 0;
     DEBUG("reading map \"" << cgzname << "\"");
     header tmp;
     memset(&tmp, 0, sizeof_header);
     if(f->read(&tmp, sizeof_baseheader) != sizeof_baseheader ||
-       (strncmp(tmp.head, "CUBE", 4)!=0 && strncmp(tmp.head, "ACMP",4)!=0)) { conoutf("\f3while reading map: header malformatted (1)"); delete f; return false; }
+       (strncmp(tmp.head, "CUBE", 4)!=0 && strncmp(tmp.head, "ACMP",4)!=0)) { conoutf("\f3while reading map: header malformatted (1)"); delete f; return -3; }
     lilswap(&tmp.version, 4); // version, headersize, sfactor, numents
-    if(tmp.version > MAPVERSION) { conoutf("\f3this map requires a newer version of AssaultCube"); delete f; return false; }
-    if(tmp.sfactor<SMALLEST_FACTOR || tmp.sfactor>LARGEST_FACTOR || tmp.numents > MAXENTITIES) { conoutf("\f3illegal map size"); delete f; return false; }
+    if(tmp.version > MAPVERSION) { conoutf("\f3this map requires a newer version of AssaultCube"); delete f; return -4; }
+    if(tmp.sfactor<SMALLEST_FACTOR || tmp.sfactor>LARGEST_FACTOR || tmp.numents > MAXENTITIES) { conoutf("\f3illegal map size"); delete f; return -5; }
     tmp.headersize = fixmapheadersize(tmp.version, tmp.headersize);
     int restofhead = min(tmp.headersize, sizeof_header) - sizeof_baseheader;
-    if(f->read(&tmp.waterlevel, restofhead) != restofhead) { conoutf("\f3while reading map: header malformatted (2)"); delete f; return false; }
+    if(f->read(&tmp.waterlevel, restofhead) != restofhead) { conoutf("\f3while reading map: header malformatted (2)"); delete f; return -6; }
     DEBUG("version " << tmp.version << " headersize " << tmp.headersize << " headerextrasize " << tmp.headersize - int(sizeof(header)) << " entities " << tmp.numents << " factor " << tmp.sfactor << " revision " << tmp.maprevision);
     clearheaderextras();
     if(tmp.headersize > sizeof_header)
@@ -802,7 +810,7 @@ bool load_world(char *mname)        // still supports all map formats that have
         if(extrasize)
         { // map file actually has extra header data that we want too preserve
             uchar *extrabuf = new uchar[extrasize];
-            if(f->read(extrabuf, extrasize) != extrasize) { conoutf("\f3while reading map: header malformatted (3)"); delete f; return false; }
+            if(f->read(extrabuf, extrasize) != extrasize) { conoutf("\f3while reading map: header malformatted (3)"); delete f; return -7; }
             unpackheaderextra(extrabuf, extrasize);
             delete[] extrabuf;
         }
@@ -813,6 +821,7 @@ bool load_world(char *mname)        // still supports all map formats that have
     rebuildtexlists();
     loadingscreen("%s", hdr.maptitle);
     resetmap();
+    int res = 0;
     if(hdr.version>=4)
     {
         lilswap(&hdr.waterlevel, 1);
@@ -852,7 +861,7 @@ bool load_world(char *mname)        // still supports all map formats that have
             #define SCALEATTR(x) \
             if((ss = abs(entwraparound[e.type][x - 1] / entscale[e.type][x - 1]))) e.attr##x = (int(e.attr##x) % ss + ss) % ss; \
             e.attr##x = ov = e.attr##x * entscale[e.type][x - 1]; \
-            if(ov != e.attr##x) conoutf("overflow during conversion of attr%d of entity #%d (%s) - pls check before saving the map", x, i, entnames[e.type]);
+            if(ov != e.attr##x) { conoutf("overflow during conversion of attr%d of entity #%d (%s) - pls check before saving the map", x, i, entnames[e.type]); res |= LWW_ENTATTROVERFLOW; }
             SCALEATTR(1);
             SCALEATTR(2);
             SCALEATTR(3);
@@ -889,13 +898,14 @@ bool load_world(char *mname)        // still supports all map formats that have
         if(q.len < cubicsize) break;
     }
     ucharbuf uf(rawcubes.getbuf(), rawcubes.length());
-    rldecodecubes(uf, world, cubicsize, hdr.version, false); // decode file
+    res |= rldecodecubes(uf, world, cubicsize, hdr.version, false) ? 0 : LWW_DECODEERR; // decode file
     c2skeepalive();
 
     // calculate map statistics
     servsqr *smallworld = createservworld(world, cubicsize);
     int we = calcmapdims(clmapdims, smallworld, ssize);
     if(we) conoutf("world error %d", we);
+    res |= LWW_WORLDERROR * (iabs(we) & 0xf);
     delete[] smallworld;
 
 
@@ -930,6 +940,7 @@ bool load_world(char *mname)        // still supports all map formats that have
     calclight();
     conoutf("read map %s rev %d (%d milliseconds)", cgzname, hdr.maprevision, watch.elapsed());
     conoutf("%s", hdr.maptitle);
+    mapconfigerror = 0;
     pushscontext(IEXC_MAPCFG); // untrusted altogether
     per_idents = false;
     neverpersist = true;
@@ -975,18 +986,18 @@ bool load_world(char *mname)        // still supports all map formats that have
 
     c2skeepalive();
 
-    loadskymap(true);
+    res |= loadskymap(true) ? 0 : LWW_MISSINGMEDIA * 1;
 
     watch.start();
-    loopi(256) if(texuse[i]) lookupworldtexture(i, false);
+    loopi(256) if(texuse[i] && lookupworldtexture(i, false) == notexture) res |= LWW_MISSINGMEDIA * 2;
     clientlogf("loaded textures (%d milliseconds)", texloadtime+watch.elapsed());
     c2skeepalive();
     watch.start();
-    preload_mapmodels(false);
+    res |= preload_mapmodels(false) ? 0 : LWW_MISSINGMEDIA * 4;
     clientlogf("loaded mapmodels (%d milliseconds)", mdlloadtime+watch.elapsed());
     c2skeepalive();
     watch.start();
-    audiomgr.preloadmapsounds(false);
+    res |= audiomgr.preloadmapsounds(false) ? 0 : LWW_MISSINGMEDIA * 8; // also set, if soundvol == 0, because no sounds are loaded (or checked) in that case
     clientlogf("loaded mapsounds (%d milliseconds)", audioloadtime+watch.elapsed());
     c2skeepalive();
 
@@ -1006,15 +1017,15 @@ bool load_world(char *mname)        // still supports all map formats that have
     defformatstring(startmillis)("%d", millis_());
     alias("gametimestart", startmillis, true);
     startmap(mname);
-    return true;
+    res |= mapconfigerror;
+    if(res) conoutf("\f3unresolved problems occured during load_world(), warning: 0x%x", res);
+    return res; // negative: error (no map loaded), zero: no problem, positive: some problems (bitmask value)
 }
 
-#ifdef _DEBUG
 COMMANDF(loadmap, "s", (char *mapname)
 {
-    if(!multiplayer()) load_world(mapname);
+    intret(!multiplayer() ? load_world(mapname) : -42);
 });
-#endif
 
 // support reading and writing binary data in config files