and suddenly....PORTAL GUNS
Edit: I had the same problem until I removed that instance from the map so make sure you don't have one in yours. It might be in/near an elevator instance if they are created in PTI.
EDIT: I tested this myself and found that a trigger that covered the elevator shaft worked for the minimum height 128 units from the bottom. elev.png
As for the elevator, It was supposed to be the departure elevator. I guess i should have mentioned that. I set up the elevator to crash before entering it and the player would have to backtrack to find a differant way out and actually finding a new departure elevator past a ratman den... So I guess I was using the wrong instance then. I wish there was a way to read the exact properties that are not dictated clearly by this program