Same for me
Defeated the Lord and then went down to the single Room in the Dungeon. There I discovered no way to open the secret door, so I tried to go back upstairs again. And then it crashes.
So I used the AreaTransition Command to teleport me to the Gilded Vale Map. Thats working, but when I try to reenter the Hold (Main Floor) the game crashes again.
And now I dont know if I can just leave the Hold be or if my SaveGame is so "broken" that it would be no use to go on with it.