Preloading external swf timeline main movie interferes?

I;m loading external swf’s with preloader in first two frames into main movie.

This main movie has only one frame. there is an action layer that says:
_root.contents.loadMovie(“home.swf”);
stop();
And a bunch of buttons that load the other movies.

If I play a movie with prelaoder in this, the preloader just sits at 100% right from the start. (he, probably counting the main movie or something)

But if I play external movie on its own, the preloader does its work.

What is wrong?
Thanxx for the help