- fixed: It seems it is not allowed to serialize any thinker before the actual thinker chain is serialized. This means that sector_t::floordata, ceilingdata and lightdata's handling had to be moved to P_SerializeWorldActors.

src/p_saveg.cpp

@@ -347,9 +347,6 @@ void P_SerializeWorld (FArchive &arc)
 			<< sec->seqType
 			<< sec->friction
 			<< sec->movefactor
-			<< sec->floordata
-			<< sec->ceilingdata
-			<< sec->lightingdata
 			<< sec->stairlock
 			<< sec->prevsec
 			<< sec->nextsec
@@ -459,7 +456,10 @@ void P_SerializeWorldActors(FArchive &arc)
 	for (i = 0, sec = sectors; i < numsectors; i++, sec++)
 	{
 		arc << sec->SoundTarget
-			<< sec->SecActTarget;
+			<< sec->SecActTarget
+			<< sec->floordata
+			<< sec->ceilingdata
+			<< sec->lightingdata;
 	}
 	for (auto &s : sectorPortals)
 	{

src/version.h

@@ -72,11 +72,11 @@ const char *GetVersionString();
 // SAVESIG should match SAVEVER.
 
 // MINSAVEVER is the minimum level snapshot version that can be loaded.
-#define MINSAVEVER	4540
+#define MINSAVEVER	4541
 
 // Use 4500 as the base git save version, since it's higher than the
 // SVN revision ever got.
-#define SAVEVER 4540
+#define SAVEVER 4541
 
 #define SAVEVERSTRINGIFY2(x) #x
 #define SAVEVERSTRINGIFY(x) SAVEVERSTRINGIFY2(x)