Help with Transitions Between External SWFs tutorial

Hello everyone. I have completed the following tutorial and found it to be very helpful and useful.

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

I do not know actionscript yet, but I am learning a lot as I go along. I am hoping that someone can help me add on to this tutorial in order to achieve a simple effect. Basically I would like to know how to make it so that when you click on a certain button and that particular section loads, then I would like to be able to swap that button in the navigation with a graphic that would look just like the button but be a different color (or whatever) and would actually be a graphic symbol (wouldn’t be a button anymore). This would visually indicate to the user which page they were on and would also prevent them from clicking a button of a section that they were already in. Hopefully this makes sense and I am describing what I want to accomplish accurately. If not, let me know and I’ll try to do better. Any help anyone could offer would be greatly appreciated.

Thanks!

Fes