Alrighty, now we're getting somewhere.
You don't need much. That drain isn't the correct drain for a shower pan liner so that's out. But not a problem.
I would first install a vapor barrier to the studs. Use 4mil or 6mil poly. Then install the wallboards using cement board.
Add one more 2X4 to the curb. The curb needs to be 1-1/2" higher.
Some of that lumber looks like treated lumber which should never be used in a tile installation unless it is KDT (kiln dried treated). Oh well - moving right along.
After the wallboard is installed also cover the curb with wallboard. Tape and bed all the joints for the bottom 9 inches up the wall.
Now, coat everything with RedGard waterproofing. Floor, walls (9" up), everything. Apply several coats and be sure not to leave any pinholes where you used the thinset in the junctures. Slop that RedGard into all of the junctures abundantly. Paint it right up to the floor drain.
Paint the curb in, top, and outside and all the junctures of the curb.
You are basically ready for shower floor tile. Once the shower floor tile is in grout it except against the walls where you will caulk that juncture, be neat. The wall tile has to cover the grout juncture at the floor.
Then tile the walls. Grout the tile, seal the grout, your outta there.
This method is slightly unorthodox but it will work fine for this purposesince you aren't off to arule start to begin with.

. No more cement, no vinyl pan liner, no more problems.