Hello All!  I am currently in the process of upgrading (learning) Preps 7 from Preps 5.3.  We are using AS Nexus 8.5 as our workflow and utilizing the EPS link files in Preps 5.3 to generate imposed files for our platemaker.  Quickly I noticed that Preps 7 doesn't accept EPS files, but requires PDFs.  I created a new workflow in Nexus creating a PDF link file instead.  When this was added to Preps 7, the spot colors in the file were dropped out.  Also, when printing from Preps 7, the only option for color handling was PDF Color mapping and the colors in the file (all CMYK, no spots) were grayed out.
I tested out the same file in Preps 5.3 and all of the spot colors in my file showed up fine.  I'm guessing it has something to do with Preps 5.3 converting the PDF link from Nexus to postscript when adding it to the run list.
So, my question is, how can I use the PDF links from Nexus in Preps 7 so the spot colors come through the same as Preps 5.3?
Any help would be greatly appreciated.
THANKS!!