It's a little late now, but if you'd centered the middle of a tile instead of a grout joint, you would've eliminated that skinny little piece on either side, and still stayed centered. That aside, it looks good so far! Ivette-- I'm getting an education right now with respect to balloon construction! The one thing that almost stopped us from buying the house was that back side of the house bows (I would guesstimate) about 6-8" from the middle to the two corners. When I first saw it, I thought the house was getting ready to collapse until someone explained that with balloon construction, that's SUPPOSED to happen! Boy didn't I feel stupid!! I'm learning, though!

dave, a couple of things: "There is a former Kerdi seller who now carrys ProVa-Mat who whines on every forum about how they took his bread and butter, but he made one good point- Kerdi doesn't want you to use modified thinset because it isn't faced to accept it well. " Kerdi doesn't want you to use modified not because "it isn't faced to accept it", they don't recommend using modified because the latex modifiers need exposure to free air to dry. The portland cement portion of the thinset cures via a chemical reaction...no drying or exposure to air is needed. But the latex modifiers found in modified thinset need exposure to free air to dry. When thinset is sandwiched between a sheet of Kerdi and a porcelain tile, the only air exposure is through the grout lines. Small tiles that would result in a lot of closely spaced grout lines, you might be okay. Large format tiles with few grout lines and little exposure to air, not so good. If you were to just smear modified thinset on Kerdi and let it cure, you'd find it will adhere quite well. The Kerdi thread you like with no photos and the Kerdi thread you dislike with photos are essentially the same thread showing the exact same steps. You wrote: "I also found this kerdi thread that has pictures...but he doesn't go up the walls from the floor with the membrane, instead he seals thinsets at the floor/wall transition- not recommended. " The method in that thread is correct. With Kerdi, any membrane overlap or at least 2" is correct and watertight. Remember you can have a 2" seam on the floor slope itself...there is also an overlap seam where every Kerdi floor membrane seals to every Kerdi Drain. Any Kerdi seam is fine as long as it's at least 2" of overlap. Kerdi doesn't have to be "lapped for drainage" like other membranes. "I am putting my mortar bed on a concrete slab. Do I need anything between concrete/mortar to prevent the slab from sucking the moisture out of the mortar before it cures properly? " You still want a slip sheet between the concrete slab and the slope. A sheet of 6-mil poly or tar paper will work fine. I've never used ProVa-Mat. Whichever membrane you use, just follow the manufacturer's installation instructions. I understand you're using cultured marble on the walls. Are you using it on the sloped shower floor too? Or will the sloped floor be tiled? If the floor slope will be covered with CM, how are you planning on sealing the seams between the sheets of CM?

I agree - but if there's a reason that's not a logical fix, then post pictures so we can see what you're dealing with.

Thanks Penny and Fori. Agree now that the "front" doesn't need to be tiled...so makes a transition unnecessary. Yay! Fori - I thought long and hard about doing a shower over tub, but decided to keep them separate. We have space for a 76" custom double vanity with storage, and a linen closet just outside the room. This is also our most conveniently located bath for guests (most often our parents) and I want to have a shower that they can use safely and comfortably. The tub is our only, so we plan to install a deeper one for soaking. The boys will only be here full time for 3-4 more years (then the tub is all mine!)