-There is the one secret retractable wall that leads to the Emperor's hologram area. Because this wall has a lip that sticks out at the very top, it's possible to get a stormtrooper caught in there. If that happens you'll never be able to retract the wall far enough again to cross, because it just keeps hitting the trooper's head and kindly going back up instead of doing the smart thing and crushing him to death.
Good observation, I knew this happened but was too late to fix it. The compiling procress sometimes creates waypoint routes automatically, and sometimes gets it wrong as you witnessed. Thanks.