u/DismalCompote4430

Onyx shower base is already installed, as is Wonder board backing for tile. (that's cardboard on top to protect) Unfortunately, three pieces of Saltillo tile are installed where the curb should be.

1. Does the tile need to be removed before building the curb?
2. If I use two by fours and Wonder board, do I wrap with Kerdi or paint with waterproofer?
3. If I wrap with Kerdi , is it sandwiched between the curb and the shower pan, or does it tuck under the Wonder board and touch the shower base?
4. Note: Saltillo tile is meant to look like a first grader made them and installed them with huge grout lines and uneven surfaces.
5. Also, do I need trim around the outside of the shower door opening, or just Schluter trim? The larger wall in the last photo will be tile also. it's a concrete exterior pony wall.
6. Should I just wall this up and make it a half bath?
7. Please be kind. I understand I'm in way over my head.

Thank you in advance.