No sounds or ambience? I swear there are a lot of sounds and ambience music, something must go wrong on your side. Maybe an engine bug, I have no idea.
About the 4th (items can go outside of the world without respawning isn't always the truth. Necessary to progress objects always respawns.
And also, rats might kill themselves because of their actions, but they will destroy everything several times faster than they will die out.
And yeah, the rest has been improved, fixed or we are looking into it, thanks for playing though. It's always worth knowing what the people might not like about the game!