I wouldn't personally move windows account/profile stuff from the system partion because of permission issues. You can just change the default lcoation of My Documents or default directories instead. For instance my windows profile is in it's default location on C:\ but all my directories for files are on a my external USB drive at K:\.
C:\ = Windows and Programs
D:\ DVD drive
E:\Sample Libries and Content (internal)
F:\ Audio (Internal)
K:\ Pics, music, office docs, vids, software install, etc etc (external USB 3)
It sounds like you now need to give your normal account higer level permission or admin rights to the root folder and all child objects on the partition with OS and programs .
You may get away with just appying this to the C:\Cakewalk folder and all it's child obects but you then still may run into issue with vst's and other programs.
Hope that helps in some way
Dean