I don't move mine with a motor for fear of this problem. I was debating a door on the coop portion, but think I've decided to definitely add one after reading this. (I was leaning that way.) I almost always move them by myself, (by hand,) and watch and listen for problems. It can be pretty slow, but fairly safe. They always squawk and flutter around, but there's usually something different when there's a problem. I think there was a head caught once, or something like that, probably multiple incidents. I don't really remember because it wasn't bad. If the outside door is open, they like to run out, so I usually close it so they don't get caught in the frame if it jerks. (There's also space under the frame, just in case.)