Those are really common sense answers that don't really address the actual question... Obviously getting a nice one piece surround would be ideal, or having the entire walls demo'd out and done with fresh tile and proper waterproofing, etc. But can't there be a possibility of a good product to use? Yes absolutely, but what are they is the question. Unfortunately, I don't have a great answer for you either, but I'm looking into it. I'm trying to find something that can go right over the tile too though, for you, just a paint / epoxy might work fine. I want something that can also be flexible enough to span cracks, but your application just going over regular walls down to the tile may not need that exactly. I haven't tried the Zinsser watertite clear but I've been looking into it, which is how I came across this, hoping to find some clues for my own. They have a clear that might work just fine for you, not sure if you used like the white for example and didn't know there was a clear. You would think someone would have a decently abrasion resistant, clear, semi-flexible coating that goes on like paint for tiled showers to seal them and make a million bucks, I'm honestly quite surprised it doesn't seem to specifically exist. For your application just about any marine clear epoxy might work too, followed by a good uv coating since you probably don't have to worry as much about cracks as I do. FlexEase was one I found that looked good. *I realize this is an old question but thought there is a possibility you might still be looking for something, or if you found a good solution, please let me know what your experience was with it.

I am a DIY'er and did a pretty significant bathroom remodel where I did all the tile work. On my shower, I used Laticrete Hydroban and durock for my walls. At all corners and at the tub flange, I used fiberglass tape embedded in thinset, sort of like your video. Much cheaper I imagine. The Schluter Band is water and vapor proof I believe. You will be using Redgard to achieve the same water management goal, so I don't believe you would need the Schluter product. All changes of material and planes will be covered with the fiberglass tape and thinset. All the fasteners will be covered with thinset. All valves are set with tape and thinset, or the product included with the valves. My valves came with a taping product that I thinset into place. Then everything is coated in the water management membrane such as Redgard or Laticrete. I filled in all small voids with thinset. I don't have a picture of the bottom of my shower pan and Durock, but I think I taped it with the fiberglass tape. It has been some time since I did this job. Below, is my thinset and taped cement board. True Confessions, I don't think I have enough fasteners, nor the right kind, in my wall, and I worry about this flaw in my shower. I had drywallers hang this for me when they did the rest of the room. I assumed they used the correct fasteners, but they didn't. They started out with galvanized nails, which I believe would have been ok, but I wanted screws, so they switched to the drywall screws. I had the Durock screws, but didn't give them to the workers, assuming they had their own. They didn't. So after they left and I saw the, I tried adding my Durock screws into the wall. I couldn't do it, I just wasn't strong enough. DH was out farming and wasn't available to drive more in for me. So I proceeded. My mistake, as I learned later the drywall screws deteriorate in cement board over time because of the alkaline conditions. I confessed to DH that the walls might fall down in a few years. He said, "well when they do, we'll just fix it." What a relief I felt, I no longer carried this burden of knowing that I flubbed up: Here is the bottom where the coating is onto the shower pan. It hard to see, but the pan and walls are totally sealed in the Hydroban. Click it open to see the bottom of the walls at the shower pan, where I taped a plastic sheeting to protect the pan. Be sure to follow the recommendations for thickness with your Redgard. This is Laticrete Hydroban: If you click the picture open you might be able to see the valves sealed with the Hydroban. This green tape is by 3M and is very strong used for taping concrete I believe. It was great to use to hold hanging tiles into place until the thinset cured. You will want this tape for your tiling job, I loved it:

For epoxy in a closed area like that you should use a toxic paint mask even with brush/roll on application. In the garage, for example, just a fan blowing over the job will do but not in the bathroom. Wear gloves too if you can. If not have a big tub of warm soapy water to wash your hands frequently if any epoxy gets on them. If you choose to use a 2-part polyurethane you'll need a special mask with it's own independant air supply. And gloves and, if you spray, a complete protective suit. Because they contain isocyanates that will absorb instantly thru your skin. And they can/may kill you. Unlike epoxy they don't wash off with soapy water. Got some on the back on one hand and had a trigger finger for 7-8 months. So make sure which type you have. Blowing those fumes out the window may be (probly is) illegal where you live so be carefull who knows what you are doing.

SAND SAND SAND. Even STIX needs sanding. I can tell you, as an adhesive primer, I was shocked at what peeled. As much as I adore and rave about Inslx (now owned by BM) and Cabinet Coat, the INSLX primer ... not so much. (BIN, Zinsser, SW, whatever, but STIX no more. Also, remember Kilz was invented for drywall.) If you really want sooth cabinets, after sanding use the grain filler. Then prime. Definitely lightly sand between all paint coats. If you don't there are mysterious little bumps and lumps that show up and you'll just seriously embed them. I've been known to take a chisel to those bumps a fingernail won't dig out, which also works on drips. I digress. Sand and wipe clean. As far as yellow bleeding through, that's usually nicotine. Disgusting, gross, nicotine. Makes things an interesting parchment color. You'll need a stain blocking primer or yes, it'll bleed through the paint. Primer is just a paint, after all. As far as the blueish tint? Who knows, but if it's coming through primer, it'll come through paint. Adhesive, stain blocking primer. You'll be shocked at how easily the paint goes on after a decent primer with a light sand before you paint. Like Buttahhhhhh. I've repainted my cabinets a few times. Before I came to understand my sliders have some type of blue tint on them. Even the samples were fine -- until direct sunlight hit them. I was always painting at night. Go figure. My point is I've done this more than most homeowners and know the "formula" is stock. Sand, (fill, sand) prime. sand, (maybe prime again, sand) paint (let dry 24 hours), sand, paint. Pet them.