QTR-Quadtone RIP

I've been successfully running QTR w/ gui for quite some time now, and
have recently discovered an anomaly in finished image size. I end up
losing anywhere from 1/16 to 1/4 of an inch from just one side of the
image. I'm running WinXP Pro, QTR w/ Gui 2.2.4, Epson 7600, UC inks w/
Eboni black, and Photorag Satin is the only paper that I think I've
seen this occur with (not that the paper has anything to do with it).
I think it's also happened exclusively with roll feed/cutter on, and
entirely on prints 16x20 and larger. I've since been printing from the
roll with sheet feed selected and so far so good with the first few
prints. 

Has anyone seen this? Any ideas? Bug in the Gui? Thanks in advance. 

Michael Gordon
www.mgordonphotography.com