Hello ptrSpzh, is there a way to contact you directly regarding an issue with the full version of Starless? Thanks!
This concerns the achievements of the GOG version of the game. They aren't working right now, but they can be enabled using the GameMaker extension created by YellowAfterlife, which you can find at this link:
https://github.com/GameMakerDiscord/GOG.gml
It would be great if you could update the game on last time, and I know a lot of other people who would be really happy about it.