Shower niche in, cement board taped and cemented...
The results of my modification...
The Whitehaus toilet lists it as a 12" rough-in but it is not, and thus, to get it away from the wall, I needed to cut out half an inch and seam it back together - I PVC glued it back together, epoxied around the seam, wrapped it several times with 1" silicone tape, epoxied once again, wrapped it several more times with the silicone tape and finally epoxied the edges.
Red Guard painted over the cement board, and tiling pattern established - tile tomorrow...
Downstairs tub/shower...
Master Bath shower...