The native version of the game (not proton) runs, and I did not test with proton because the native version worked. I will say that I did not play for very long in my testing, I went as far as the menu, briefly messed with the ship design menu, and briefly ran a campaign level. In my relatively brief testing I didn't notice any problems, but I don't have extensive playtime to attest to whether it crashes after a period of time. At least it is working, as before this game used to not even launch. I should also note: in order for the game to launch you have to use the "run through istrolid.sh" launch option. Using the standard "Play Istrolid" option causes steam to think the game is running, but it never opens. The way to get this option is to launch the game from the steam library, not from the desktop shortcut or taskbar, and it will give you the option "run through istrolid.sh". You should pick that one.