as2 partial preloader - difficult issues

I am working on a preloader that will load multiple clips to be played sequentially as “slides” on the stage of my main movie. Here is the difficult part - the preloader is designed to, depending on settings, either download all clips and then begin playing them, or it will download the first few and then start playing the first clip, while continuing to download the remaining clips off-stage.

Are there examples of such a preloader?

Thanks