DVD ROM Empty

I'm new to apple and idvd. I am making a dvd of some slideshows I made in iphoto, I have the box checked for "Always add original slideshow photos to DVD-ROM" in idvd preferences. I imported the slideshows into idvd, and checked out the dvd-rom file, and to my dismay it was empty, I was expecting and hoping to see that the pics of my slideshows would have automaticly showed up there. Did I do something wrong or will they show up after I burn the dvd?