ActionScript 1/2 :: Detecting RollOver Without Button?

I have made a movie that loads many sub movies into itself and I want an information box to appear  when the mouse pointer rolls over each movie. Some of the movies just play and loop so to get the box to pop up I just load the movie then attach an invisible button over it in the same size and position, which works fine. The problem is that some of the movies are interactive and have internal buttons that respond to the mouse rolling over them, so if I put a external button over them their interactivity is blocked. I also want to avoid putting custom code that targets the parent movie into the loaded movies so I don't have to adjust every movie I want to load. Is there a way to keep the interactivity of the loaded movie but still detect a mouse rollOver?
 
The scale and position of the loaded movies changes continually, but the only way I can think of of achiving what I want is to write code that continally calculates the size and position of the loaded movies and compares the position of the mouse pointer with them and brings up the info box if a hit is detected. This would be fairly complex