I'll admit i'm pretty fairly green for this particular project, but i have done a tile floor in a laundry room that turned out great, and I believe i'm capable once I get over this hump. here's the issue:
when i built my house 7 years ago i had the them rough in a bathroom in the basement. the bath/shower drain pipe basically gradually emerges from the concrete at the typical 1/4" slope, but it was only about 6 inches from the wall. for the tile shower i plan to build i basically have to turn the drain at a right angle and bring the extension out about 18 inches. keeping with the 1/4" slope puts the top of drain pipe at a good 1/2" above the concrete floor. adding the p-trap and the 3-piece drain obviously raises things even more, putting it in my opinion too close the top of the typcial 3 2x4 stud height of the curb.
so my questions basically revolve around whether or not i need to raise the subfloor by maybe adding an inch or so of concrete before i start the pre-slope of the shower pan? can cement board be used to raise it ? does it need to be raised at all, or maybe the curb can be 4 2x4s rather than 3?
check out www.wedi.de , while a European company, they have a US distributor branch. They've got an interesting horizontal drain that (I think) they've gotten approval for that might solve your problem.
Important note - I'm not a pro
Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013