Originally Posted by Walkland
Finally found the solution to my crashing, posting it here in case anyone else has a similar problem. Mine was different, in Cazador's palace there's that dead girl that has the sapper curse cast on her, I had dragged that corpse out of the room using a spell so that I could loot the stuff inside the room. That body with the curse had killed the vampire girl on that floor, but she was bugged as dead but with full hp. I hadn't noticed and then went and killed Cazador. Just throwing it out there so folks know it could also be somebody in Cazador's mansion. Good luck to everyone!

Thanks a lot! You've just save my playthrough. Exactly same case.