Now it is starting to look like a shower.  They use really light weight but solid backerboard known as Wedi board.  They extended the short wall you see on the left by about 10" which we had several reasons for requesting.  This allowed us to add recessed shelves in the shower for shampoo, soap, etc by the main shower control, allows us to add a recessed cabinet for our ironing board and iron inside the toilet room on the adjoining wall, and it makes this short wall wide enough to hang art on now.