I backed up my full music library to DVD about a month ago. Since then I have downloaded more songs from the Store and also added some of my own CD's. I noticed today that I am missing some of my store purchases from my main library but i know they are on my backup. Is it possible to only restore a part of my backed up library? I only want to restore the missing parts and the entire library because then my new material (not on the backup) will be lost!!