OP here. Appreciate all the replies. I have since burned through most of the 49' roll, with perhaps 5 feet of usable prints. Noting more frustrating than to see your work come alive and elegantly presented, only to have the surface marred by scratches. Maddening.
I am wondering if changing the paper thickness setting would help. In my Epson 7800 it is set at the standard 3mm. But I have since learned that the paper is 3.3mm. Since you cannot use fractions in the setting dialog, it would mean going to 4mm, which I will try. I also use the "wider" platen gap setting. Interesting that there is no "widest" option in the print driver, though I have seen it mentioned on line. Perhaps with other printers. In any event, I would appreciate any feedback regarding the potential effect of using a wider paper thickness setting. Basically a hail Mary pass at this point.
Thanks
David
PS: Mark, I did try flattening some roll stock, without effect. I have 13x19 cut sheets which do survive better - but still not perfect. I think the combination of paper thickness, stiffness and delicate surface are the hat trick.