Embed Notice

If you watch the video, when the door unlocks and then opens, there's a second guard standing inside the room to the left of the opening door. That guard is actually standing very slightly too close - the very corner of his bounding box intersects the door's path as it opens. So what's happening is the door starts to open, slightly nudges into the guard's toe, bounces back, closes, and then automatically locks. And because there's no script to deal with this and re-open the door, you're stuck.