

Runs fine out of the box.
works flawlessly with Proton 8.0.5 and probably higher. 25 hours straight with no issues whatsoever.

Works just fine with Proton GE.
It just works.

Game won't start
No matter which Proton version, the game will simply not start up. Not even a black screen or anything, it will just do nothing for a few minutes until Steam decides it's no longer running.
Runs smoothly with no tweaks

I'm running forced Proton Experimental by default. loading feels rather slow considering my hardware (and my active Steam library lives on an NVMe). game slowed to a stutter after about 5 or 6 hours of playing (no idea why); restarting it solved the issue for me.

I use NixOS, but it is the same kernel and steam/gamescope setup as SteamOS itself, so it should work exactly the same on SteamOS.
Freezes and crashes after very long playing time (more than 3 hours). May be an issue with the game itself.
If you are using a PC instead of a SteamDeck, consider using Proton GE. You need a mouse and keyboard as the game does not support controllers.
Flawless experience

No performance or game play issues with any Proton (Experimental, and 8.0-4) version used but does have missing ingame video on the main menu and in the tutorials. Recommend using GE-Proton to fix this.
Works great aout of the box

Using an older Proton version, the game starts but shows a black screen and save/load screens are non-functional.
I tried a variety of versions of proton and various launch options but nothing improved matters. I'm still new to this so hopefully someone more experienced can find a solution.

This runs just as well as Oxygen Not Included and really has no problems running. This is just the playtest
This is just the playtest and could and probly will change. Just hope it does not break compatablity.