I submitted a help request to Profantasy earlier, but have figured out the issue myself in the meanwhile. I suspect customers will have the same problems as I did if you're running 64-bit Windows XP or Vista. The error in question was the patch informing me that it couldn't find the product, even if I dropped the executable right into the same folder as CC3.

To resolve this I uninstalled everything and re-installed into a non-standard folder. By default the software installs to "C:\Program Files (x86)\Profantasy\CC3", and it would appear that those parenthesis are, perhaps, the problem.

I chose a custom path of "C:\Profantasy\CC3" and the CC3Patch7.exe ran and updated the software without a hitch.

Hope this helps folks. I know I searched back through the forums here and couldn't find anything salient.