Well, on question 2, either put down some thinset or make a slurry of portland cement before you throw down the deckmud. Make sure you cover it before it skins over. On a slab, you want it bonded, and either of those will bond it in place. If it was on a wooden slab, then you'd want something to prevent the wooden deck from sucking the moisture out of the deckmud before it had a chance to cure...not the case on a slab.
If you overbend the lath for the curb, it will act like a spring clamp. Be careful not to tear the liner when you put it over the curb. Then, you cover it with a sticky brick mortar. A good place for reference material on shower building and anything tiled is www.johnbridge.com. Look in their 'Liberry' section.