Crash when colonising dragonstone

Whenever I try to colonise Dragonstone in the scouring of lorath bookmark (I haven't tested if it happens in other bookmarks too) of the andal invasion submod, I initially gain the colony fine, taking the primary holding, but when I unpause the game and am granted the other 3 holdings, the game crashes. I have tried this as a few different rulers that start nearby, and it always crashes. I have seen AI valyria successfully establish a colony there without it crashing.

I'm playing with only the AGOT mod and Andal invasion submod enabled.