The itch client issue is actually because of the game being on 100% off sale, there's a bug with it. If you'd like I can send you a download key (which should let you download through the client just fine) or you can download through the itch website instead :)
Hey! If you're having trouble with downloading it through the itch client/app, try downloading from the website instead if you're able. (If not, I can send you a download key that should let you download through the app)
