My guess would be there is still remnants of the old data in the registry and re-installing didn't get rid of them, because it wasn't uninstalled first. What I would try is making a backup of the download first so you don't lose it.
If you haven't yet contacted Robert, I would try that next. Explain to him what happened and give him the authorization request code along with the error message, then he can give you an new activation code to get it up and running. It might take him awhile to get back though, sometimes he's pretty busy.