I would'nt suggest to use domain wide policies for this purpose, but its ok.
OK. You have to use the loopbackprocessingmode for these workstations.
OK just enable the loopbackprocessingmode under: administrative templates\system\group policies
Put it back to the default state.
Yeah. Userpolicies are for users. (exeption: loopbackprocessingmode)
Bye
Norbert
PS: Take your hands off from No override an No inheritance