During the Aksha boss fight, you are supposed to be able to break the windows in order to deal with her regeneration. However, this does nothing since she simply hovers over you and attacks you while staying in full darkness. It's as if the light does not spread dim light vertically, only horizontally.
Also, when one of your characters dies while being drained to 0/0 hp, there is no way to raise them, not even with a Raise Dead scroll. They fall back to 0 HP while the Revivify counter restarts.