hmmm back to you. let's see:
a half zip on the takeup bar to attach to the backing which has the other half.
a half zip on the backing front bar (against you) to attach to the bottom of the backing.
a half zip on the roller for the top of the quilt, with the other half on the end of the top.
right so far?
how does the top of the top attach? do you also attach the batt? or float it?