1)I saw it before, but honestly it doesn't make sense, the BGM is in the game files, and I can't seem to recreate it. Works normally for me.
2)Same thing.
3)Can you provide a screenshot of any area next to that? There's a lot of maps in the mountains.
Probably related to Khas'es light script. I've had the issue for a while. It triggers in areas like dark caves, where torches provide their own light. Honestly it's a pain.