Note: This issue is resolved in Aperture 3.4.2. If you use custom command sets and updated from an earlier version to Aperture 3.4 or 3.4.1, use these steps to resolve the issue:
- Open Aperture.
- In the main menu bar, choose Aperture > Commands > Import.
- In the file selector sidebar, click your user folder.
- Press Command-Shift-Period at the same time on your keyboard.
- In your user folder, navigate into Library/Application Support/Aperture/Command Sets.
- Choose the custom user set you'd like to import and click Open in the file selector.
- Repeat for any other custom command sets you'd like to import.