I lost my game progress. I saw a sort of fix on a post in the game's Steam community, but the files provided there didn't have all the areas I have already cleared.  I found out that there were two folders with the game's data, 'C:\Users\itch-player-...\AppData\LocalLow\Adriaan de Jongh\Hidden Folks' and 'C:\Users\username\AppData\LocalLow\Adriaan de Jongh\Hidden Folks', in the latter were the .data files with my saved progress. I copied both files to the first folder and it worked.