That has nothing to do with the installation issue when using the itch.io client. The installation script isn't configured properly and nothing downloads.
It isn't so much that the installation script isn't configured properly as that there isn't an installation script. The game's just a basic executable file; it's intended to be downloaded and played normally. I'd like to support the itch app integration eventually, but I didn't even know about it until a few weeks after launch, so it's going to be a future thing.