I'm apparently very bad at choosing site names or there's something wrong with that piece. Seems that no matter what I choose for a site name, I'm shown a message stating that I can't use that name.
You should post up an FAQ or more information on how this works before asking users to login with their Dropbox account.
No example site?
Doesn't work. "This app is in development mode and can't accept more users. Contact the app developer and ask them to use the Dropbox API App Console to apply for production status."