Well, just in case, make sure that the files of the game are extracted. Go to the file directory and extract them from the Zip folder, and try again -- if you haven't already.
Right click on the game in your library (if you use the Itch app, or use its game library) and click Open folder in explorer. It should take you to where your game is installed to. If you see a Zip folder, extract its contents into that folder and try loading up the game again.
