Everything on the 1st Floor. Here's the first floor layout.
You'll be led into one of the four loading rooms (doors to show space are closed) - you load up and your door opens. The open space is what you saw in the promo video with the First Order officer inspecting the ride vehicle. You then continue through show space, winding through the hallway and come upon the AT-AT room. The 2 cars separate and each take an elevator to the top, - that;s the end of that half of the first floor.
The other side of my drawing (bottom-left side) you see the 4 (marked green) elevators coming from the 2nd floor (escape pods) - after they crash land, they roll out and follow the curved path to the unload area at the bottom. (4 grey boxes) the cars then travel back to the start area to be recycled for more passengers.
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