I know exactly what you mean with the weird angles. Some of them are optical illusions, where a tall vertical wall looks like it's tilting slightly over you because of the placement of lights and a less tall wall on the other side of the hallway. Other areas have very slightly rotated wall textures. It's often a bit disconcerting. If someone wanted to make a slightly creepy and vaguely unsettling map they could open up this one in Dromed and see how the author did it.
Don't give up, bro. You're doing a great job researching all these. Thanks for reviewing old FMs.