Files are not saving correctly any more

Good day. I hope you can help me with this, I am really stuck:
Version is 2024.4.1.152; runtime 2024.4.1.201 on Windows 11.

I write .ini files to the save directory. They go to appdata/local/(gamename).
Game save location is set to %localappdata% in options for Windows. So, this work OK.

However, I wanted to create a demo for the game, so I duplicated the project, and named it gamenameDEMO.
When I read game_save_id, it displays the correct location: appdata/local/(gamenameDEMO).

But...

Files are not saving correctly any more