This may not look like much because of the simple animations but let me
describe to you why this is a very elegant and efficient way to structure
a site (insofar as ActionScript 2.0 and Object Oriented Programming are concerned).
The simple buttons for this page have only a very little amount of code in them;
When they are clicked they don't do anything but dispatch a message. This message
says what the button is named and what movie it should load. There is an external file,
BtnEventManager.as who's only job is it is to listen for these messages (ie., Events, hence
the name BtnEventManager.as). Once it hears a message it knows what button sent it and what
movie that button wants to load into the main movie. That external file then tells all of the
other buttons, via another external Class file called BtnStateManager.as, to goto their primary
state and tells the button who just sent the message to go to it's clicked state (in this case
pink). It is very smart to pull the functionality out into two seperate files because if there
is an error somewhere down the line in one of the external files it can only effect one part of
the button functionaliy and the error will be much easier to isolate. This is great for huge
projects like the ones I work on. So when the movie first loads it loads in the intro movie. The
intro movie is also told to listen for messages but the difference is that the intro movie and
subsequent movies listen for a different message (stageHandler if you must know) that tells
them that they are to start their exit animation and what movie to load after they have completed.
So when a button is clicked any movie that is on the state (say intro) will play it's exit
animation (this animation can be either via ActionScript or traditional tweening things around
physically on the stage). In either case the move on the stage will finish it's exit animation
and then load onto the stage the next movie (which it heard in the message). The next movie will
do the same. On a side note the different external movies also will disable all of the buttons
until they have finished their intro and/or exit animationas clicking buttons while a movie is in
the middle of a transition usually has devistating effects (i.e., break your site).

So there you have it, a very Elegant way to structure a site using AS and OPP. Just so you know
this site structure also makes use of many different .as files including but not limited to the Tween
Class for AS motion and also XML for content (XML allows the client to make simple text changes that
are pulling into the movie at runtime instead of compile time, if you don't know the difference then
don't worry about it.