Your best bet is to ask for help on the #knossos channel on the HLP Discord
Note that we can't guarantee that a specialized Linux distro, such as Pop!_OS
, will be able to run Knossos/the game well or even at all, even if it's based on a general-purpose distro (Ubuntu in this case).
As for updating the Knossos build instructions, RL is unfortunately too hectic right now for me to set up an Ubuntu VM (on Windows) and produce reliable setup instructions. Perhaps I can do that sometime later this year, or maybe someone else can do it sooner.
Hope that helps.