QTR-Quadtone RIP

Hi - Happy Holidays!  
Questions:  I ran many head cleanings over several days and I have 
not been able to get a completly clean nozzle check, but only with 
the cleaning solution (Number 8 position), (there are a few blocks 
missing in the pink area), they are always in the same positon; every 
thing else is fine with the rest of the nozzle check.  (K-7 inks with 
a Niagara IV continuous ink system.)  Can this effect the quality of 
your prints, since this is just the cleaning solution? 

Also:  I am using a new computer with the latest QTR 2.5.2.  The old 
computer was runnig QTR 2.5.1.  I have set everything the same, old 
to new, same paper, ink, same Ink Limit of -1, and same Gamma of -11; 
both computer are PC's (the old one runs Windows XP and the new one 
runs Vista.)  After printing a photo of a print that I did on the old 
computer and comparing them, the one done on the new computer is 
flatter looking.

The Real Questions:  Can the newer version of QTR, or anything else, 
effect this change?  Do I need to re-adjust the Ink limit and Gamma 
settings?  Can the Cleaning solution nozzles effect this or any other 
change?  Last, why would something like cleaning solution be blocked 
anyway?

Thanks for any help.... Mike G