I think that I used to know this.  For SSD reasons I don't want any sample data on my system drive.  VSTs OK, sample libs no.
Toward this end I have my DimPro libraries on my e:
I just want to know how to get the Program Browser to use
E:\SmplLibs\Cakewalk64\Dimension Pro\Programs
as the base address instead of
C:\ProgramData\Cakewalk\Dimension Pro\Programs
I expect that I will need to use REGEDIT to do it but I'm not sure which key to edit.
thanks in advance
ddt

I do not believe there is a registry entry for DPro programs. The data in ProgramData are not samples and unlike samples, the programs do not take much space. In my case the ProgramData part of DPro contains a little over 7000 files consuming a little over 56MB. If you really want to move it, use a directory junction.