I've checked around and the dev responded to a Steam thread like "delete anything with '.save' in the Data folder" but I tried that and it didn't work. (There wasn't any .save file in my Steam folder for the game?) I also tried reinstalling but Steam has cloud saves.

Please refer to this guide: https://www.speedrun.com/coloring_pixels/guide/lackx

Sweet, thanks. Could "Bonus" and "Community 1" be added as categories since they're technically free (and thankfully not too long)?