Those are different issues.
The blackness of walls is caused because, if you come from hydlaa, and you load the magicshop map, it doesn't found cached lighting for different objects (one of them the texture for magic shop walls) and thus shows completely black.
When you logged off, and back on, you only loaded magicshop map, and that avoided the error of "not finding a cached lighting" for magicshop walls.
StarsAndBars_1018 are you running the game with the option "keep maps loaded" on ?