Transitions between external swfs

Hi

I’ve created a site using the great tutorial on transitions between external swfs at:

http://www.kirupa.com/developer/mx2004/transitions.htm

I’m able to navigate between the main swfs (sections 1-4), but what if I’d like to call eg. section3.swf from within section4.swf (from a button within the body of section4.swf, and not simply from the main header button at the _root level)

thanks very much
Aidan