Not sure if Wrath is still checking the forum, but I just bought this game myself this weekend.
The registry edit works fine for me - however, if you're running Vista the "real" registry entry is not the one under
HKEY_LOCAL_MACHINE.
Vista has registry virtualization for older programs to make registry entries that would otherwise have global impact to instead be limited to a single user. E.g. if you had two user accounts setup on your machine, you could each have your own distinct settings in Nexus; in Windows XP you could not since the settings were stored at the machine, and not user, level.
To find the real entry search for Nexus under
HKEY_CURRENT_USERVirtualStoreMACHINESOFTWARE. That's the one you want to edit.
Note to any of the WSGF mods coming across this thread. You may want to update the
solution thread . The bit about Vista and the registry virtualization likely applies to any of the older games which store their settings in the registry. I'm not sure that there's one convenient place to put this info though, probably just have to update individual solution threads as people come across them.