


Proton or bust
Native Linux version spreads itself to BOTH displays.
Native Linux version fails to shutdown properly, leaving ghost process (and some visual artifacts) which can't be terminated by average gamer-on-linux.
And even then, the right answer is "maybe". You'll have to jump through some hoops to make the game use your primary display to the fullest. But it's well worth it.

The native version works ok
Some people reported problems with the linux version but on arch the game works fine on steam. The original 2003 version is only for windows so you have to redownload and open it with bottles or something else.
Player 2 will need to play on keyboard and mouse.
Working out of the box. No modification needed. Everything recognized. If playing with someone, the player will need to play with a keyboard and mouse.
I have DRM-free version of crimsonland from Humble Bundle. Linux native version works badly (can't handle two screens, freezes, crashes), so tried windows version with Steam Proton. Works great out of the box
Had audio issues with native. Had to fix a monitor issue, but other than that it worked perfectly.
Screen spread out between two monitors, changing settings in game crashes game and forced me to system reboot. Had to unplug second monitor in order to fix this.
Previous save was working on native, switching to proton wiped it. (previous achieved on windows)