Play SWF file within movie

I have tried several methods of getting an SWF file to play withing my movie - all with no luck. I am using a button to direct the main movie to frame 4. Then - at frame 4 I want another movie to play. I am getting the gray outline of a movie - but it will not play. What have I done wrong?

I have tried making a movie clip for frame 4 and then using this code....

on(press){
loader1.loadMovie("nameoffile.swf");
}

(This code comes AFTER the code that moves to frame 4 and stops.)

...and I have tried simply importing the movie into the frame. I can't think of what could be missing.