hi! i run both games on the steamdeck w/o issues. desktop mode -> what you want to do is to download the game through the browser and not the itchio app on the steamdeck. this is bc you want to dl the windows version and not the linux version. add the .exe as a non steam game to steam. game mode -> go to settings, compability and select proton. i find that using proton 7.X works best for me. proton is necessary to run win games on the deck.
viel spaß beim spielen!