The registry key you want to look at for where the Dim Pro path to the multi-samples is:
HKEY_LOCAL_MACHINE\SOFTWARE\Cakewalk Music Software\dp
If you navigate to the above registry key, you will see 'Multisamples Folder', and that is where Dim Pro looks for its samples and such.
IF you are going to change this path, you may want to consider backing up the Registry, and perhaps separately writing down the original path pointed to by the Multisamples Folder key. (you could just type it or paste it back in, should you goof up on specifying a valid new path and want to revert, rather than restoring your entire Registry).
Anyways, IF you want to move the multisamples, I suggest you COPY the folder and paste it to its new location, followed by then editing the registry to point to the new location, followed by trying out Dim Pro, PRIOR to deleting the original multisamples folder.
I do not remember if once this is done whether or not you have to refresh the browser in Dim Pro to attach to the new location.
Anyways, the above is where the folder is pointed to in the registry.
Good luck,
Bob Bone