Preloader Transition for Dynamic Files Tut

Hi,
I used the tutorial “Preloader and Transition for Dynamic Files” by Claudio
http://www.kirupa.com/developer/mx/preloader_transition.htm
for a project - it works really very fine.
Now I have just one problem:
I have to load the whole site.swf into a movieclipholder and now I don’t find
the paths anymore. An example:
That movieclip I use to load the site into is called “siteMC”
The code on the buttons are:

b1.onRelease = function() {
if (_root.section != “profile.swf”) {
_root.section = “profile.swf”;
_root.transition.gotoAndPlay(“closing”);
}
};
b2.onRelease = function() {
if (_root.section != “gallery.swf”) {
_root.section = “gallery.swf”;
_root.transition.gotoAndPlay(“closing”);
}
};
b3.onRelease = function() {
if (_root.section != “photos.swf”) {
_root.section = “photos.swf”;
_root.transition.gotoAndPlay(“closing”);
}
};

So I change the paths to: “_root.siteMC.section = gallery.swf” and so on.
That works also. But now, there is a script in the 1. frame of the transition movieclip that executes the loading of the first content swf:
“_root.section = “profile.swf”;”

Here I tried everything from “_root.siteMC.section” “_parent.siteMC.section”
and so on - nothing happens.
Do anybody know what I have to code here so I can load the first swf or maybe some other solution?