sometimes I locked to 30 FPS occasionally when doing mundane stuff

I think if you set it to fullscreen it would be extremely laggy because it is not compatible with the Steam Deck's native resolution (windowed at 1280x720 ran perfectly fine 60 FPS, but fullscreen was at like 10-20 FPS)

In one of the later chapters (I believe chapter 9 or 10) I was unable to pass a certain cutscene as the game entered a bugged permanent loading screen once the cutscene finished. I tried loading from multiple previous saves but this didn't work either. To solve this, I switched to Proton Experimental which fails to load any cutscenes and it allowed me to continue with the game by effectively skipping that cutscene, after that portion I just saved and switched back to Proton GE.

Also, I did not really hear any audio for a majority of the cutscenes.