I want to warn translators (if they are here) that the script has once again been proofread from the very first version. So there may be some difficulties with the old translations.
As for the problems with your old saves and why they may be glitchy. Either it's because I updated RenPy or I misplaced variables somewhere in the code. Or it's because you used some mods. But I'll double-check it tonight.
Also because of the RenPy update, I had to change the Scene Gallery code a bit. Now if you open a scene, you have to restart the game to unlock it in the Scene Gallery. I know this is very inconvenient, and I'll try to fix it for the next release.
PS. If you're asking me why I updated RenPy in the first place, as far as I know, the looping animations play much smoother in the new versions. This was one of the main reasons why I updated. And a few more minor ones as well.