Since Nexus Mod Manager for Linux fizzled out, I was excited to find a decent mod manager. It has built-in support for about 100 games, but adding other games seems pretty easy. I pasted in the Steam ID and path the the .exe of a proton game (MineMogul), and then everything just worked.
Not sure, first I’ve heard of that too…screenshots look similar, I’ll have to check that out too, thanks!