What are your specs? I'm interested in trying the DLSS mod but I have a notebook 2080 so not sure how much that will help.

Also avoid the Steam discussion forum. Awful awful place right now.

Really wish GOG could could release NOLF1+2 -- I'd love to have them in my library.

There is a mod on NexusMods that gives you a lower quality 'low' preset that I found helped me get a more stable performance on my deck.

There is a modded Low ini available on Nexusmods that helps on Steamdeck. Hope that the performance gets better over time though.

I'm in Act 3, about mid way through, and definitely Act 1 shines above the other 2, but Act 3 so far is more enjoyable than 2.