Most Flash developers add preloaders to the beginning of their movies so that all content is loaded before playback begins. By default however, Flash exports component data in the first keyframe (before your preloader), which defeats the purpose. Here’s what you do so that component data is loaded after your preloader.
Right click on the copy of SlideShowPro for Flash in your FLA’s Library panel. Select “Linkage”. Uncheck the “Export in First Frame” option. Click OK.
Open File > Publish Settings. Click on the Flash tab. Then click on the “Settings” button next to “ActionScript Version”. In the settings dialog, change the “Export frame for classes” from 1 to an empty keyframe on your timeline that’s after your preloader, but before SlideShowPro for Flash on your timeline. For example, if your preloader was on frame 2, and your instance of SlideShowPro for Flash was on frame 10, you could pick any number between 3 and 9.
Now when you publish your FLA the class files are exported after the preloader, thus creating a more accurate preloader at the beginning of your movie.