Thanks for checking in - I've traded a couple of emails with Roy but so far he has no ideas about it. I sent him a long email last night detailing my workflow to make sure I'm using the print module correctly (couldn't find documentation on it). I'd like your feedback on it as well. I will try reinstalling the driver and printer and let you know - in the meantime here is info on how I'm working.
I've focused my testing on 8.5x11 sheets to minimize expense with the exception of the 12.5x24 sheet I was trying to do for a client. In addition to the GO problem which is frequent, I've noticed one glitch when printing and image. My test image is 7.3x9.2 - sometimes when I print it on the 8.5x11 sheet a thin line of the image (1/16th") prints then there is a gap of .5" and then the rest of the image prints. I did one test of 1) start computer and printer up 2) open print module 3) open test image and print (see screen shot of setup) - first print comes out with line, I hit print again with new sheet and it prints fine. Next day I did exact same steps and both prints came out fine.
The GO problem is more erratic, prints different amounts of the sheet before stopping, I've even seen it print some GO skip part of the sheet, print some more and then stop prematurely. With an image it is always exactly the same failure (1/16th" line), although it occurs intermittently.
Since I am usually printing different size files and want to use paper economically I always setup a custom page size in the page setup to be somewhat larger than the image (always more than the default margins). I do this printing from rolls as well and have not seen any problems so far doing that but have not been doing a lot of roll printing til I get this resolved. Also for GO printing seems you pretty much have to print in sheet mode.
A normal workflow to print a 16x20" print from roll would be to create custom page size of 18x22" for example and trim off excess paper from roll to end up with 18x22 sheet. Measure that, reinsert sheet in print in sheet mode, set up custom page size to 18x22, open 1x1" white GO file and print with GO curve. If starting with a sheet it's the same, the initial custom sheet size is whatever size sheet I put in printer.
BTW printing on FAP with the type5 curve did not work well - I've been unable to coat them to do final testing because of this issue but it's clear just from looking at my test print that the curve is far too heavy in the quarter tones. We'll get back to that once I can reliably print GO.
I was unable to upload my screenshots using the attachment manager for some reason - all four failed with a red exclamation mark but no other indication. They are .png files. I will send them separately to you via email.
Thanks for the help.