ActionScript 2.0 :: HTML Loads A Preloader That Then Loads The Actual Flash Movie?

Everything is embedded in an HTML site. The HTML loads a preloader that then loads the actual flash movie. Inside this movie I created a few buttons, inside a scroll bar movie clip. I want the buttons to load a whole new movie inside the same html. The code I'm using in the button is simply:

on(release) {
loadMovie("new_movie.swf", 0);
}

The problem is that it works beautifully in the Flash movie tester but doesn't do anything when tested inside the browser, embedded in the HTML. I think the problem is that the HTML embeds as an object the first movie, the preloader for the menu movie, not the menu movie itself.