Don,
your problem with the loupe seems much more seroius than mine.
Try to find out, if the problem with the Loupe is system wide on your Mt. LIon mac or only your occurs in your current user account.
To check this, log into a different user account on the mac and check Aperture with a few test pictures. You may want to create a new account if you do not have asecond account. Don't change any standard settings; just try out the loupe in Aperture.
Does it work in the other account? If not, I'd reinstall Aperture. But if it does work, it would indicate that the settings in your main user account need fixing. Try, if removing the Aperture preferences apple.com.Aperture.plist from your user library "/Users/YourUserName/Library/Preferences" will help, see on how to do this.
Aperture 3: Troubleshooting Basics
Also remove the mirrored file in /Users/YourUserName/Library/Containers/com.apple.Aperture/Container.plist from your User Library.
The user library is hidden in Mountain Lion. To unhide it, use the Finder's "Go" menu.
- Quit Aperture.
- Click somewhere on your empty Desktop to bring the Finder forward, then you'll see "Go" in the Finder's main menu bar.
- Then hold down the options key ⌥ until "library" appears in the drop down menu. Click Library to open and navigate to the "Preferences" foder. Remove /Users/YourUserName/Library/Preferences/apple.com.Aperture.plist and
/Users/YourUserName/Library/Containers/com.apple.Aperture/Container.plist
- After removing the files to the Desktop, log off from your User account and log on again - otherwise the changes to your library may not take.
Removing the Preferences will reset all entries you made in the Preferences oanel to their default. other presets however will stay.
Regards
Léonie