Sorry to hear you're having trouble! Unfortunately I can't personally provide Proton/Wine support, but it is deck verified from Valve and should be playable on Steam Deck if you launch it through Steam—a Steam key is included with your Itch purchase though, which should just work without any further configuration. If you have any further issues, please contact me at support@loveconquersallgames.com !
You can find instructions for that here: https://itch.io/docs/buying/already-bought