Preloader Help!

Hi everybody i’m building a website with a common preloader for each of the externals swf files that will be loaded. Then i have a home, about, gallery, etc buttons. So everytime you press a button it will play a MC called transitions. This transition MC has about 30 frames where the first 10 are a label called “closing” (a transition) and the next frame (11) is where the MC will be on stand by waiting for the external swf to be loaded and immediately after the swf is loaded it will play the next 19 frames that is another label called “opening”.
Everything is working fine but what i need is that while the preloader is preloading a swf file, it’ll display the percent amount and a progress bar. I know that make a preloader is not difficult thing, but in this particular case i can’t make it, cause i don’t know where to add the script. In the main movie i have a layer that contains a MC called content and it has the following script:

onClipEvent (enterFrame) {
percent = (this.getBytesLoaded()/this.getBytesTotal())*100;
if (!loaded && this._url != _root._url) {
if (this.getBytesLoaded() == this.getBytesTotal()) {
loaded = true;

I also have inside the MC called transitions on frame 11 the following script:

loadMovie(_root.section, _root.content);

And i have an actions layer in the main movie that contains this script:

home.onRelease = function() {
if (_root.section != “t1.swf”) {
_root.section = “t1.swf”;
about.onRelease = function() {
if (_root.section != “t2.swf”) {
_root.section = “t2.swf”;

Now, what i need to know is what code and where i should add it to get a percent and a progress bar while is preloading an external swf.
I know my explanation is quite messy but i hope you’ll understand the idea.
Any help will be apreciated.