ActionScript 1/2 :: Control An Externally Loaded SWF?

I'm working on an flash movie and the interface is a small town (simiar to "doritos.com" and "comcasttown.com") if you reference both the doritos and comcast sites their little movie runs smoothly. I have several elements in the town. For example, one of the elements is an airplane hangar. When you rollover the hanger, I created a movie, the doors open and an airplane flies out of the hangar. I have several little movies throughout the interactive such as this. I created the hangar animation as a seperate swf file. In my main movie I created a button, on rollover it loads the hangar swf into an empty movieclip. When I publish and view the swf it plays slow and choppy. First, is it possible to write actionscript to load the external swf ,but it stops on the first frame of the animation and when you rollover it continues to play.To put it all in a nutshell, I want to create several buttons throughout the movie with loadmovie functions, once the swf movies are loaded I want them to stop on the first frame of the animation and when you rollover loaded swf movie I want it to continue to play the animation. Should actionscript be applied to the swf movies first and preloaded into the main movie. And what will make the movies run smoothly once it's published and viewed in a browser.Also if this makes a difference, I created the animations in after effects, exported them as FLVs imported them into flash and exported them as swf. Again it runs really slow and choppy