Thanks for all the suggestions. Although it may be
premature, I think I have resolved the issue. I have been using the front
loader to avoid pizza wheels. I have used a piece of inkjet paper to facilitate
getting the Pictorico into the printer, then removed it, and loaded the
Pictorico by itself, and printed. This has worked fine for many months with no
marks. The marks are a new issue. I have recently shifted to Cone inks and
thought that might be the issue, but based on the advice that the front feeder
was for thicker paper, I left the paper with the Pictorico and loaded them
together and printed. The results are promising, but I will have to make more
negatives to be sure. I appreciate everyone's help. I have no idea why this
would all of a sudden become an issue when I have had success doing it the
previous way.