I'm just waiting on my steam deck to charge so I can curl up on the couch with this for a few hours before bed.
EDIT: I tried it out on my laptop while waiting for the deck to charge, and I'm seeing some bugs in the software renderer with missing textures for semi-transparent objects like floor grilles, so I'm switching back to OpenGL for now. If anyone at Valve wants log-files or information on my setup in order to reproduce, I'm happy to provide it; my email is in my profile.