Marvin XD is for managing books already installed in your Marvin library.
To add books from calibre to Marvin, start calibre with your iPad connected and the calibre connector active. Select books in the calibre window, then click Send to device in the calibre toolbar. Close the calibre connector to return Marvin to its normal operation after adding books to Marvin.
After you've added some books to Marvin, then you can use Marvin XD to manage those books as described in
the first post in this thread.
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