Yeah, I install off a disc and get the same message as Raptor when trying to use MultiSH3.
My savegames and careers automatically go to:
Local Disc C\Users\HomeUser\MyDocs\SH3
The root file is located in:
C\ProgramFiles(x86)
I'm wondering if that is insufficient permission for the mod (it should be) and I should create a separate area in D drive