How to reproduce: open Hellbound MAP14 and proceed to an elevator which will rise up as soon as you step on it (impossible to miss, only one way to go). By moving around while the elevator is going up and especially by bumping into walls it is possible to get stuck so that you'll be unable to get off the platform without noclipping. The player's view height will be at the floor level (see the attached screenshot).
The platform will continue to function normally after it has risen completely (by stepping onto it from above or pressing on it from below) and it is still possible to fall victim to the bug. But it only seems to happen when it's moving up, not down.
This seems to be an engine bug and not a map bug. By inspecting the map in Doom Builder, I haven't found anything unusual in that particular place. The bug happens both in GZDoom 3.1.0 and the latest devbuild.
P.S. Had to convert the screenshot to JPEG to attach it. IMHO, the forum should allow attaching screenshots produced by GZDoom without processing them first...
