Okay good to know. I'm aware of a number of the rendering quirks you mentioned, and the ones you mentioned in the 64-bit build are there in the windows builds as well. I'll attempt to address a few of them moving forward. I have no idea what causes the 32-bit linux build to have audio issues but I'll look into it.
Where were you able to get outside of the map?
Right in the beginning room when approaching the robot receptionist. While facing the robot, about a foot away, the rendering seems to freeze and I seem to be able to zoom right past the robot.
As a suggestion (if you haven't already), try using Ogg Vorbis encoding for the music files for Linux, as Vorbis is supported out of the box in most distros.
Not sure what's up with that spot, I'll look into it.
I can definitely make the music and audio all .ogg as well, but that one will take a bit of time.
Thanks for the comprehensive feedback! I hope you can still enjoy the experience amidst the weird issues.