Lord Inquisitor SeruFollow

go left, up steps, then down hall one of the rooms on the right, which has a fake wall to the S between 2 book cases, left in next room, and there's aportal on the wall in there.

Portal takes you to maze level. Use hieght filter on map to see how to go, thre's a portal in the bottom left of map maze. That portal takes you to the hallway that surrounds LIS's room.

Hopefully this helps, but hard to describe in text, without actually walking it and telling every turn , etc.

Yther Ore.