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Photo Mechanic's Dropbox uploader would need "full Dropbox" permissions in order to create folders that you can share outside of your account. When we had initially applied for our Dropbox production key, with "full Dropbox" permissions, our request was declined. We therefore had to submit a new production key request and this time with only "app folder" permissions.
Unfortunately there is nothing that we can do to change this. I apologize for any inconvenience this caused.
-Jerry