Even though the game still waits to perform the Steam Deck compatibility test, after multiple tests accross different Decks, the game fully runs from beginning to end with full controller support.
Also, since the game has a linux native build, it works out of the box. If you encounter the issue where the game doesn't start or any Cloud Sync issues, Steam might be downloading the game with Windows proton compatibility.
To fix this problem you can manually select the Linux Native build from the Settings->Compatibility option on the game.
If you encounter any other issue that I missed while playing, make sure to notify me in this thread so I can fix it right away.
Thanks for your support!
Astrow