De-activate CIS

Was writing a guide today for a customer of mine on how to apply their COMODO Pro license in V10. While doing so I went through the process on my system running CIS Premium (the free version) with an old license key. Come to find out that the old key still has a few days left on it and it activated without a hitch. Problem is, I don’t want my own system activated and want to resort back to the non-activated free version. Is there any way to do this without completely uninstalling/reinstalling COMODO? I have configuration settings and rules created and I really don’t feel like going back and redoing all of that. There doesn’t appear to be a way to do it through the UI but perhaps there’s a registry key or license file that can be deleted to restore me back?