I’m hearing that the game is currently much more stable on Linux, for some reason. Haven’t had a chance to test it myself.

Is it just visual for the player, or does it cause NPCs to see you?

The Starlight spell (school of Illusion) casts but does nothing. If you look directly down it suddenly starts working.

The Unofficial ES wiki mentions some of the newly introduced bugs. https://en.uesp.net/wiki/Oblivion:Remastered_Changes