- Go to the Flickr website and log in to your account
- Go to the Apps By You page in the App Garden
- Click Get another key
- Choose Apply for a non-commercial key
- Enter a name and a description and check the two waiver checkboxes before submitting
- Copy the Key and the Secret to the fields above, and click Save settings
- Now you can go to the Import tab, and you'll be prompted to log in to Flickr from Piwigo