Hey, sorry for the late reply. My knowledge with Linux systems is very limited, so I'm probably no big help here. It sounds like an issue with Ren'Py in general, not a game specific thing. Eruption Imminent does only use Ren'Py base components, no additional plugins.
If you still have the same issue I'd recommend asking on a Ren'Py or Linux related forum. Alternatively you could join my Discord and ask there. There might be some people around that can help.
No worries, thanks! I figured it out, just had to set SDL_VIDEODRIVER=x11 not the other thing.
Looking forward to the next chapters :) love the branching writing so far -- I'll just +1 a comment I saw somewhere else, hoping the game avoids a "sandbox mode", that really takes me out of VNs.
Also, if you're open to a suggestion, I'd love to have a "movie mode" where I can just choose up front whether I want a siren/kitten/cq run and then just let it play :) thanks again for replying, totally happy to see wherever the game goes next [and you can totally ignore me haha]!