If you take the actual leaders on and off the rail, how do you make sure it stays centered consistently?
On my machine, the leaders are duct taped to the pole, so the center never moves. I have zippers on the other side of the leaders. I pin or sew the back of the quilt to the zippers. I can unzip, hang the quilt to inspect. I also use this for the 'Stand and Stare' part of a custom quilting job, but only after the quilt has been stabilized.
I purposely try to not get pictures with the hanging rail in my pictures, so I had to go back a bit to find one with the zipper. The rail is on a pulley system, wrapped with fabric and the same side of the zipper as is on the machine. The other side is on the top of the quilt. When I first got the machine, I bought about a dozen 144" zippers, so I have lots of ways to use them.
http://wheatridgestudios.blogspot.co...rose-lane.html
I'm actually going to be replacing my leaders tomorrow, along with new rails and a major upgrade to my CompuQuilter. This should be an interesting project!