I assualted a town without walls as Casse and the battle started without a problem. Then I assualted a town that had walls and got a CTD. So the CTDs have something to do with settlements with walls. Also, I redownloaded and reinstalled EB and it didn't work. I am playing on 1.5 patched to 1.2, maybe that is part of the problem? If there is no fix for this I guess I will have to wait for 0.8 to play the barbarian factions.