2015-06-03 by richard@...
I had the same thought as Roy, and was going to suggest that you use a slightly larger 2-ply board than the paper you are printing on. If you align the right edge as you are looking at the front of the printer and back the paper off the front edge of the backing board by about 1/4 inch you can tape down all 4 and corners and have less chance of movement. I first found this problem trying to print separation negatives for platinum and nothing I could do with the front feed would print two negatives in exactly the same spot (using the same file and same position registration targets).
Do you have the same pizza wheel problem when using the rear manual feed?
As for the curled paper jamming on exit, you take a spare or damages sheet of paper and stick it through the front so it looks like this ___---_/ <---printed sheet- and the curled edge of the printed sheet is guided under the rollers. I have to do the same thing with some papers in a 7900/9900. It might be easier and more consistent than printing with backing board.
Richard Boutwell