Find a sailmaker with lots of Nacra experience and most of your questions will get answered. Glasser comes to mind along with Skip Elliot and the other sailmaker out of Florida (can't recall his name but he always advertizes in Catsailor)

Upwind on my 5.5 Uni mast rotation with the boomless rig is easily controlled via the boomless traveler. Readily adjusts the mast out of rotation if needed to fit wind conditions. Downwind, boomless traveler is released all the way and rotation is controlled via a front crossbeam mast rotator. No big deal for me.

Jake is right though, make damn certain the sailmaker understands the sailcut differences between boomed and non-boom rigged sail geometry. Ask for references and then call them.

Good luck, Tom G