printing canvas on Pro9000MkII
I spent some time, inks and canvas (Inkpess, Canon and H. Monet) using my 9000 MKII. All canvas have different look and handling. Now I use Monet because I has no flaws like rest two but the most expensive from them. In case of Inkpress canvas (gloss or matte) both are glossy I can barely see a difference. Canon canvas very matte like your Monet but last one reproduce tiny details and has nice texture.
I have no such problem feeding from front load. Maybe your printer has jammed or more serious defect present. I tried front load, it works but I like rear load better and printer doesn't mind to do so. Sometimes I cut off small corners on front edge of sheet to help front edge get through first set of rolls. Main reason I use read feed because if you choose "canvas" ICC from media menu you must use front feed. If you do so, you can only use large size of sheets and as result unpredictable color management (no matter calibrated your equipment or not) and lots of waste.
I use canvas for "reproduction" of paintings from art galleries and originals have glossy finish. To get closer look I use Gloss Varnish and after that contrast and colors looks different. I use some set of ICC profiles to get test prints on small (3.5x5) sheets. And I can tell - original ICC Monet canvas from Huhnemuhle in many cases is not the best profile.
Also I have sometimes marks on front edge but it is not a problem for me because who needs borderless prints on canvas? I think the best way to avoid marks - do not use borderless printing. Some inks spilled off media on printing area. Open printer cover and look at black foam. You will see spilled inks exactly at 3.5, 4, 5 8.5, 11, 13 inches from right side and the most spilled area - point "0" on the right.
It is just my experiences and I hope it will help you.