I have two questions, which are preventing me from making any inserts for all these cases I have.
First, I was wondering if anyone had any experience with printers, and new what was causing mine to mess-up and seemingly scratch the print job.

I'm using a Konica Minolta Magicolor 2430DL.
And finally, the images I'm printing from home are all printing out just a tiny bit longer than can fit in the Universal Game Cases.

The height is fine, and exactly the same height from Staples (I can't print there anymore, I got lucky once since I guess the girl was new and printed them for me.)
I've used MSPaint and PS:CC on Win8 with the 2430DL printer, and even MSPaint on Win7 with an Epson XP-410. I've changed the page setting from "Fit to 1 by 1 Page(s)" to "Adjust to: 100% normal size," changed page size to Legal (and using Legal paper,) centered Horizontally and Vertically, and even tried multiple print jobs with the margins set at both 0.5" and 0.1". It's always too long. All the files are 3366x2100 pixels, created or edited using 'Shenske's Universal Sega Template,' and can be found at the BOX link in my signature.
Any help would be appreciated. I'm close to just printing out spines only and using that.