QTR-Quadtone RIP

Wanted to throw a question at more experienced QTR users.  I currently run Cone NK-7 / 
R1800 / OSX.  I had better results running a Quad setup rather than the 7 inks because the 
quads, believe it or not, gave smoother transitions from highlight to shadow.  NK-7 should 
be better in theory but I feel like the light to mid positions lack density.  I see this especially 
when printing images that move quickly from highlight to shadow, such as strong lighting in 
portraiture.  The NK-7 prints have so little ink in the highlights that they look blown out.  The 
shadows on the other hand look like they run a strong line when next to blown out 
highlights.  I get better prints even using the Epson ABW on a 7800 possibly because the 
highs and mids have more density.  

So my question to the group, is how do you change the density of the NK-7 curves provided 
by Cone?  I thought I read somewhere that they were proprietary.  Has anyone else made 
their own NK-7 curves on a R1800?  I already tried the QTR icc route but it didn't solve the 
problem.  Has anyone else seen this problem also?

I posted at the Piezo group but didn't get any responses.  Pretty anemic on that site.  Thanks 
in advance to anyone who responds.