The beginning of the maze starts in the back of the building and you work your way forward. The building is two levels. However, the maze is only on the bottom floor. The second floor is for make-up and a break room. That last couple of scenes are generic scenes, which will allow them to change and add as more seasons of the show are completed. The strongest part of the maze would be the sets, very detailed.
In the photo below, you enter through the marquee and go through switchback queues which will lead you to the back of the building. The exit is the beige building just to the left of the marque.
Photo Update: May 14, 2016 - Universal Studios Hollywood by
InsideUniversal.net, on Flickr