I did it. I have the kohler Greek tub installed in an alcove. I ordered the tile in bead kit. But my contractor had something similar that he liked better so we used it. It is a plastic length of material that gets installed around the tub and then the tile comes down over it. We have used the tub as a shower for over two and a half years with no problem.

It depends on whether the tub is cast iron or acrylic how well they work, I think. The Greek is acrylic and the plastic flange can essentially be fused to it like you can fuse two pieces of any plastic with certain adhesives. Porcelain probably doesn't take to this as well.

Is there any way you can just return the tub and get the proper flanged kind? I know a delay of a few weeks can seem enormous at this point but a few weeks will be over soon and a slow chronic leak around a tiled in bathtub lasts forever (unless you take it out and put in a flanged tub).

Problem arises when the tub you want to use isn't 60"L, the only size where flanged alcove tubs are widely available. There are only a handful in the 5-1/2' and 6' sizes, so you'll probably want to use a drop-in tub that the manufacturer recommends for use with a tile-in flange kit.