QTR-Quadtone RIP

I had to reinstall 2.5 because v 2.6 would not print on my Mac (10.4) 
and epson R1800 3MK system.  Problem is, I can access the QTR functions 
in Print mode in Photoshop CS3, but I cannot find the QTR folder as I 
want to start building my own curves.  Last time I had 2.5 running 
there was a QTR folder under Applications.  No matter where I look OI 
cannot find the QTR folder.  Any ideas?
Thanks
Paul