A new version came out on November 4th, so you need to download it again for it to work
Does it say v2020.11.17i in the top left corner when you open the game? That is the most recent version. Make sure you're looking at the right file after you download it. You might be accidentally opening the wrong one.
If you're having trouble downloading the game from itch.io, add the game to Steam with the key on your download page. It'll update automatically from there. You could also use the itch.io app if you don't want to use Steam.