Do you simply want to add the swf in its current form to a new movie? I think I may be misunderstanding the question....
If I am understanding, do this:
Add a empty movie clip to your new fla and give the MC an instance name (such as container). Place the empty MC on your stage where you want the already finished swf to appear then use loadmovie to load the swf file into your new fla.
I hope this helps. Good luck.