This GUID - B54F3741-5B07-11CF-A4B0-00AA004A55E8 - is the GUID for VBScript. However, the entries under it were invalid. There was also another HKEY_LOCAL_MACHINE entry that was valid. It appears that Windows will go for the current user entry first.
I renamed the registry entry under HKCU and re-ran the installer and all is now well.