Okay, I figured out something interesting about this. I have a crash that I can reproduce. Always crashes at a particular turn. It exhibits all of the symptoms of index corruption. The game keeps lists of all the units, all the cities, etc, I think those lists are becoming corrupt.
Its all game engine stuff, I may be doing something wrong with how I add or remove objects.
So to test this I saved my game through the worldbuilder. This writes the game out as a scenerio, all units, cities, relations, etc are preserved. But the game is going to reload as if it was a new game. All of the objects and actions stay the same, but all of the indexes and internals are rebuilt.
It worked. No more crash.
Could some of you with crashes test this same thing. Just reload your game thats crashing, preferabbly right before the crash. Then go into the worldbuilder and you will see a save option in the worldbuilder menu. Then exit to the main menu, start a new game (it doesn't matter what the new game is), then once your in that game jump into the worldbuidler and reload your worldbuilder save.
Let me know what you find out.
Thanks,
Kael