Hello,

Hugslib log:
https://gist.github.com/HugsLibRecordKeeper/996bab7ea3915c122cb3f14f87c68d1f
I found that when I loaded a previous save the cave entrance and corresponding exit had vanished, and the cave had begun collapsing, though it hadn't been doing that when the save was made. The same issue happened a couple auto saves back as well. I was able to load far enough back with the same cave that the entrance/exit were fine.

I had used maybe 10 caves so far, so its not a permanent problem.

The one thing that happened that was different was that there was a landslide, and a piece of collapsed rock landed on the top left tile of the exit. This didn't affect the exit while I was playing though. The further back save was before this landslide.

Actually I decided to get off my ass and test it, that is the problem. Here is another log, where I deactivated most mods, used the dev quick test, dug a hole, waited, landslide on the exit, load game, and exit vanished, cave collapsing.
https://gist.github.com/HugsLibRecordKeeper/7b5ba9d3eef0e18b1d85362ecd321294

Thanks for the cool mod :)