The front is attached to the inset in a lapped seam. You're supposed to do this before putting on the inset facing/lining, but I find it's easier to do the latter first. Here, I've pinned the inset on with its lining pushed out of the way.
After the front is pinned on, the inset lining can be pinned down over that. The pins are oriented so that they can be taken out while machine-stitching. I ended up hand-basting this first, though, because it was easier to keep all the layers lined up attractively and the gathers positioned evenly (at the time of the photo, too much of the fullness was toward the right).
Pattern back -- only the robe gives any with-nap yardages at all, and that's only for a 58/60" width.