Hi,

   Yes, PDf reDirect does support CMYK color separation, but the color data must be provided in that format from the program you are printing from. For example, in CorelPaint, I choose the CMYK print output option, and in PDF reDirect, I choose the same option in the Printer Output >> Color Model >> CMYK.

   For the differences, there is a long list shown on the Features page on the web site (here). Look for the Green/Red checkmarks that will show you if it is applicable to the Freeware and Pro version, or just the Pro version. As you scroll down, it will list only the features for the Pro version.

   Honestly, your best bet is to try the Pro version as part of the 90 day trial. This will give you an opportunity to see if the extra features are worth it. You can switch between "Freeware Mode" and "Pro Mode" inside the program, so there is nothing extra to download.

   Cheers!