QTR-Quadtone RIP

Hello,
I'm a happy QTR licensee on a Mac for many years, currently  using Epson 3800 and 7800.   I've never printed color until now and I am having terrible trouble. Strongly suspect it's the "double profiling" problem or whatever it's officially called, where color management gets applied twice--once by Photoshop, again by printer. The prints come out extremely dark/muddy and colors way off.

Here is my question: Is it possible to print color images to the 3800 and 7800 with the QTR Print Tool and is this a way to avoid the double-color-management problem on color images? If so, is there a recommended procedure?

Mac 10.7.5 (Lion) Photoshop CS6

Relatedly: If anyone can point me to a for-dummies guide to fixing double-color-management, I will be forever grateful. I've tried various recipes but can't get a procedure that actually works. Probably missing a  simple step; can't for life of me spot what it is. Much paper and time wasted so far,etc.

Many thanks in advance , best regards,
JP