It’s a known issue that a few people suffer from, and I haven’t solved it yet. If you’re on Steam that you can temporarily fix it by downloading the older Alpha22 build. You need to right click on the game in your library, go to properties->BETA and choose Alpha22 save compatibility.

If you don’t mind helping me a bit, I’ll get in touch with you in the new year and send you a few special builds that will help me pinpoint the issue.

Sorry for this bug. I’ve tried figuring it out with the help of a few users, but it requires a lot of sending builds back and forth, and I haven’t pinned it down yet. Did I already get your contact details in case you’d like to help?

The issue should be fixed in the most recent patch, although I didn’t manage to understand exactly what the problem was. If this keeps happening please let me know.