I was just browsing through co-op games, and found this and was happy to see that I had access to the prototype/demo version from a bundle 4 years ago. Itch isn't making it very clear if I just have access to the demo or the whole game, but either way, when I try to download, it says that there is no download available.

So, is it still available, even in demo form, via Itch, or should I go get this on Steam? Thanks for any help!

doesn't seem to be available :( checked steam and cant find anything

There used to be a playable prototype on this itch page, but it seems like it’s no longer available. It was always only a prototype and never access for the full game. Possibly they hoped to avoid confusion between getting the game here and on Steam so they removed the build.

Find it here on Steam. I had great fun with my kids playing the prototype. I bought the Steam version, but haven’t played it yet (backlog!).