Plan 19 does not have a reverse loop.
Im not 100% sure on the 22" track pieces, but they would have to go somewhere on the right side of the layout in the inner loop. One near the top and one near the bottom. When you start putting that part together try them in a few places to see where they fit best. Just make sure that you keep an even number of 18" pieces between them.

Wife got me this set for Christmas. It comes with the 22" track. Set it up on a 4X8 table. It runs right out to the edge. I agree that it looks real bad on the 22" curves. If I want to run this train I'm gonna need a bigger room.