I am getting another crash, I'm including the crash report and the saved game.
If it duplicates it should cease as soon as you try to end the turn
I can replicate the crash. Investigating now.
It appears that if a civ is eliminated, but a new one is generated to replace it (presumably either due to a civil war or the creation of a colony), the new civ inherits the dead one's culture even if it's on the other side of the planet!
In the screenshots below, the Sioux wiped out the Mayans, but not too long afterwards there are again a full 18 civs and the old Mayan cities have a majority Russian! culture.
I wondered if there might be problems with reusing a player ID, which can happen once there have been 18 civs in a game but one is wiped out. I'll see what I can do. Other than city culture, have you noticed anything else the Russians have 'inherited' from the Maya? Diplomatic attitudes perhaps?