I have moved a library to an external drive. The library contains a Slideshow that has music tracks from iTunes. When I tried to play it, the music does not play and I see a yellow exclamation point indicating the music is missing. I would like to re-link the slideshow to the music. Does anyone know an easy way to do this. I would prefer not re-placing all the tunes into the slideshow since I have changed the volumes and edited their length. Thanks.