trouble Loading large external swf

I have a large swf (2mb) loaded into an empty movie clip on frame 1 in the main timeline of my movie. It runs fine locally, but not on the web. It plays a few frames then stops for about 15 seconds and then plays.
I have a preloader set up, but it doesn't even show up on the screen. I have 2 scenes "loading" and "movie".

Here is the code on the first frame of the loading scene

if (_framesloaded>=_totalframes) {
_root.gotoAndPlay("movie", 1);
} else {
_root.gotoAndPlay("loading", 1);
}

On frame 1 of the movie scene
_root.puzzle_mc.loadMovie("puzzle_test.swf");

any suggestions? Thanks so much!