Stop an external swf file from playing

I have a large (25MB) video file that was given to me. It’s a swf file that someone created from a quicktime movie. I can’t just use this swf file as it needs to fully load before playing. I have created a preloader that loads the external swf and shows a progress of the external swf file. However, the external swf file starts playing. I want to stop the external swf from playing until it fully loads.
[LIST=1]
[]var maskStart:Number = -150;
[
]var maskFinish:Number = 60;
[]var maskMove:Number = maskFinish - maskStart;
[
]var myLoader:Loader = new Loader();
[]var fileURL:URLRequest = new URLRequest(“externalMovie.swf”); // approx 25MB
[
]myLoader.load(fileURL);
[]myLoader.contentLoaderInfo.addEventListener(Progre ssEvent.PROGRESS,fileLoaded);
[
]function fileLoaded(event:ProgressEvent):void {
[]var percent:Number = event.bytesLoaded/event.bytesTotal100;
[]logoMask.x = maskStart+ maskMovepercent/100;
[]//trace(percent);
[
]pcLoaded.text = Math.round(percent) + “%”;
[]if (event.bytesLoaded == event.bytesTotal) {
[
]removeChild(logoMask);
[]addChild(myLoader);
[
]}
[*]}
[/LIST]