Under windows 200x, the resolution is quite simple (grant local activation rights to wss_wpg for the component, as per http://support.microsoft.com/kb/920783)
Under 2008 R2, the "edit" button is greyed.
That's because the ownership of the corresponding registry key is to "trusted_installer", not you (even as admin). Go to the key and take possession of it, and the edit button will be enabled.
The key used by the IIS WAMREG admin is:
(Do not remove trusted installer rights)