-If a unique NPC you imprisoned escaped that can mess up the world states because they're technically not dead or imprisoned anymore and they have no home to go back to, but they're usually still in the world somewhere. First place to look is their original home cuz they could still be roaming around it in the police station as a slave and slaves don't count as prisoners so just knock them out and they'll be arrested, other than that they could literally have been captured by slavers and taken to the other side of the world or something so RIP (vanilla issue)

-Don't import without unchecking dead NPCs too much while messing with the world states, otherwise Kenshi will break and forget to use world states and you'll have to start over. This seems to happen when either you imprison important NPCs, or leave them for dead out in the world. They either must be confirmed "dead", or never imprisoned if you want to import without unchecking dead NPCs and not break the game. (vanilla issue)

-Town icons are supposed to update when you capture them, for instance a ruins icon would turn into a village icon. Also ruins debris still spawn in captured cities. Importing fixes this but importing without unchecking dead NPCs is dangerous for world states! (vanilla issue)

-For Brink to be occupied, you need to also kill the leader of the Reavers in Ark for some reason. (prolly my fault but I have no idea why)