Lag problems on only 1 map, repeating error in output log

[kunyomi]

I just started a new map, same size I always pick (2 sizes bigger than the standard), mods installed are EdB and Combat Realism. Running A14.

For about an hour nothing was wrong but suddenly the game would grind to a halt when I try to speed it up, and this bug keeps popping up in the log:

System.InvalidCastException: Cannot cast from source type to destination type.
  at RimWorld.FilthMaker.MakeFilth (IntVec3 c, Verse.ThingDef filthDef, IEnumerable`1 sources, Boolean shouldPropagate) [0x00000] in <filename unknown>:0
  at RimWorld.FilthMaker.MakeFilth (IntVec3 c, Verse.ThingDef filthDef, Int32 count) [0x00000] in <filename unknown>:0
  at Verse.Explosion.TrySpawnExplosionThing (Verse.ThingDef thingDef, IntVec3 c, Int32 count) [0x00000] in <filename unknown>:0
  at Verse.Explosion.AffectCell (IntVec3 c) [0x00000] in <filename unknown>:0
  at Verse.Explosion.Tick () [0x00000] in <filename unknown>:0
  at Verse.ExplosionManager.MapComponentTick () [0x00000] in <filename unknown>:0
  at Verse.TickManager.DoSingleTick () [0x00000] in <filename unknown>:0

It repeats itself infinitely in the log at the very end.
I've got no idea what all this stuff means, what it looks like to me is something is trying to explode but failing?

Hope someone can help me out.

[milon]

The mod version must match the RimWorld version or it WILL cause problems.

And it looks like Combat Realism hasn't been updated since A13.  That's likely your problem right there.

Also, which EdB mod are you running?  There are several.

Finally, if you're still having trouble, a full output log would be much more helpful (see my sig for instructions).