Preloader for an external library

What I'm using:
Macromedia Flash MX 2004

What I'm trying to do:
I have an external preloader linked into my flash file. It loads the main flash file quite perfectly. I'm trying to then use the same preloader to load an external flash file.

In other words, after the main flash file loads, I want another progress bar to show the loading of the next SWF.

The problem:
Like I said, the preloader works perfectly for the main site, but while trying to load the external SWF, the preloader shows the movie clip as completely loaded. After about 20 seconds, my image (the external SWF) shows up.

So, it's not a matter of the picture showing up, but simply that the progress indicator is broken. I'm guessing it's looking at the panoGoesHere movie clip and sees that the clip itself has loaded, but it doesn't look at the ActionScript. If that is the case, how do I make the preloader monitor the loading progress of the external SWF?

I have:
MC: panoLoader on main timeline
|__MC: panoGoesHere
| . |__ActionScript on frame 1 (see below)
|__preloader
. . .|__ActionScript on the clip (below)

ActionScript on frame 1 of _root.panoLoader.panosGoHere:

Code:

---

this.loadMovie("panos/main-entrance.swf");

---

Actionscript on the preloader:

Code:

---

onClipEvent(load){
        preLoad=(_root.panoLoader.panosGoHere.getBytesTotal() * .98);  //percent to preload
}
onClipEvent(enterFrame){
        gotoAndStop(loadedIndicatorFrame());
}

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