Problems with Classes and Scrollpane

I have a basic preloader set up on the main timeline, which uses an onEnterFrame function to preload the content. Also in the publish settings, I have classes exported on frame 3, and on frame 2, I have set down all the mc’s that have been exported from the library (to make sure they are available). When the content is loaded, I have the movie play frame 3 (blank) and stop at frame 4, however when i test the movie, all the scrollpanes that have mc’s loaded in are blank… is there any additional steps to take to ensure the mc’s get loaded properly?? sry if this has been answered before…