Nintendo Switch Pro controllers now work! I made some updates and played through the demo both on a Windows PC and SteamDeck using an official Switch Pro Controller to confirm.
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ORIGINAL POST:
First off, I want to thank everyone that's played the Isle of Reveries Demo and either left a review or posted their feedback in the Community Hub!
It's come to my attention that there are some bugs when using a Nintendo Switch controller (Pro Controller, USB GameCube controller, etc). I believe this comes from the engine I'm using to build Isle of Reveries in.
I'll be trying to resolve these issues, but I highly recommend playing with an Xbox controller (of any kind) or using the keyboard. I apologize for the inconvenience.