Right. Played it, and I thought it was a nice little map. The red key was pointless though, as you could just have given the player the blue key instead of the red key, not bothered with the red key bit at all and sent him straight outside and it'd have made no difference. Heights and stuff where "real" architecture is concerned is always a bit dodgy, so I'll not bother going into detail about that. Otherwise it was a nice little blast. Not challenging but not boring either. I managed to miss some of the monsters (dunno where they were) and I felt a secret or two wouldn't have gone amiss, but oh well. There were one or two walls that looked like they might open on the map, but didn't whilst I was playing - perhaps they don't work?
To stop the door tracks sliding, tick the box next to "lower unpegged" on each door track line. This renders them from the bottom up, meaning they won't move up with the ceiling of the door.
Here's the bugs and texturing errors I noticed whilst playing:

The red key floats when you lower the floor, due to being too close to the window ledge. It also seems that the floor itself goes down too far or something, judging by the way the shadows and light effects seem to leak into the floor. You seem to have used GZDoom to test and I'm sure it works fine there, but it looks quite dodgy in ZDoom.

Just a texturing issue, but not aligning this here where you've used shadows is painfully obvious. Pressing "a" in 3D mode whilst looking at these walls should sort that out.

This shadow sector seems to have gone into the floor, either before I pressed the switch to lower the red key or afterwards. I think it might have been tagged the same as the red key sector.

God knows how you did those cliffs, but they HOM like hell in ZDoom. My guess is it's a skybox or portal hat's not set up properly, but gotten away with in GZDoom.