Flush shower finished and problem with sealing

The page basically stands out into open space. I had also considered the tiles, but the highest point is 2 cm and then slopes down to 0. The installed tiles are porcelain stoneware, but they will probably break or I won't be able to cut them cleanly unfortunately.

Just turn the track around and slide the piece that is normally under the tile so that it is under the vinyl, and at the bottom by the tile, make a silicone joint and that's it.

Is that strong enough? The vinyl at the transition isn’t firm. You know what I mean? I once found a picture of the conversion on my phone and edited it. On the left, the marked area is now the vinyl and towards the wall there is a 2 cm slope that runs down to 0 towards the room.

If you glue the rail to the 'wall' with silicone and then make a silicone joint along the bottom at the tile transition, it will hold tight. The only thing then is that the approx. 1mm metal, which is normally embedded in the tile adhesive, will be under your vinyl. I don't know if that is noticeable.

Since it is supposed to be permanently watertight, I would spend 20 euros here and get a cartridge of MS Polymer. My home shipyard, and not only mine, even seals hull penetrations underwater with it. Permanently watertight. MS Polymer, brand name Pantera, is hardly available in building materials stores away from the coast, but it is freely available and can be purchased by mail order. Unlike silicone, it is extremely adhesive, even on fingers, paintable, sandable, permanently elastic, and highly water-resistant. Also usable as an adhesive. It cures more slowly than silicone. Give it an extra day. Karsten

I have now ordered the rail on Amazon and am simply going to try to slide it under the vinyl the opposite way to how you intended. I also found the adhesive on Amazon for 8 euros. Unfortunately, I am not allowed to post links, otherwise I would have done so to check if it is the right one. Would regular construction adhesive possibly also hold here? The other product apparently seems really difficult to work with if you read the reviews.