Help loading swf /how to debug

Hello.I am really stuck. I am having a great deal of trouble getting a movie to load in an empty movie clip. I am hoping I’m missing something simple.

I have a button with the instance name SPS_btn on a layer I’ve called buttons.
Below the button layer i’ve got a layer called movie clips that contains an emptymovie clip called mainStage_mc. I want to load a .swf into into mainStage_mc. both the buttons and their actions occur on the first frame.

I have used this code but it not working.
on (release) {loadMovie (new002.swf, mainStage_mc);
I just get a blue area but the movie does not load. I can run the movie fun locally by clicking on new002.swf file.

i also tried the behaviors panel,
which produces this code but it also doesn’t work:

on (release) {loadMovie (“new002.swf”,mainStage_mc);

//load Movie Behavior
if(this.mainStage_mc == Number(this.mainStage_mc)){
loadMovieNum(“new002.swf”,this.mainStage_mc);
} else {
this.mainStage_mc.loadMovie(“new002.swf”);
}

//End Behavior
}

for some reason it will load if i use loadMovieNum () but the registration point is in the top right corner and i don’t want that.

What’s the best way to debug this?
When i use test movie the output window dosen’t show an error but something’s wrong.
how can I test if is a path problem? A problem with the loaded movie?
or a problem with something else?

the movie new002.swf is 393KB. I tired making a smaller 2kbmovie using the code above and it wouldn’t load either.
Can someone shed some light on this?