Dear Hybris, I'm terribly sorry you hit this issue, but I think I have hopefully solved it now!
(It seems the build I had uploaded didn't specify to the Itch.io app/launcher what kind of platform it used, but I have made sure the platforms are assigned now.)
From what I've read, the issue is specific to the itch app, so if the error persists, you should still be able to download the game directly from the gamepage in browser (link here).
However, obviously I do want the issue to be fixed properly, so please let me know if it now works for you! I haven't used the app myself before, so I will test it later when I'm back home.
Thank you so much for taking the time to inform me of this, I really appreciate it and I apologise for the hassle it caused.
Best wishes, Cerise