Windows,Mac and QTR printing

[Jeecee]

Hi everyone

I'm using VirtualBox on an iMac and Windows XP.
I'm using a special software to print on a "B&W" only printer (6 different dilution of blacks). Since on the Win side, the gui is more user friendly, I go from OSx to XP without a problem

On the Mac side I had to buy a special piece of software to be able to print with "no colour management". This software is bypassing both Adobe and Apple colour controls. On the other hand, I can always print on the Win side but, without that special printing program. My question is do the iMac still manage some parts of the colour since two prints, made from the same file, are not the equal.
On the Win side, I use a program called "QTRGui" and can print directly to the printer (although I know that the OSX in underneath since I emulate XP). On the Mac side, with the same file, I print through PrintTool (to bypass any colour management.

Any explanations about those different results from the same file?

Many thanks