Unload a movie but gotframe or reverse frames

Question

Ok, I have a base movie with a background that holds the
buttons/nav and main logos. I had loaded a content movie in there
with a stop at the last frame. What I want to do now when I click a
nav button, say '3D graphics page' the 3D graphics page loads the
3D graphics movie (know how to do that) and the content page
unloads gracefully, say playing the frames backwards to where the
page started and unloads as the pages all come in nicely. Maybe
just to go to another frame for a mini animation to ease out of the
page to transition to the loading movie.
All the nav buttons would need to be able to call the
diffrent movies up whilst the previous movie unloads gracefully so
I guess actionscript on the buttons wouldnt work?
Maybe the onUnload command? Never used it.
Can I acheive this?
Thanks

Answer 1

The only thing that comes to mind is to use some modulus math to determine when you are in a frame that should be a stopping point. This would work as long as you have spacing such as you explained...25, 50, 75....  If the currentFrame%25 == 0, then that is a frame to stop in.  As far as the act of keeping things moving, you want to employ an ENTER_FRAME event listener so that it continually processes the prevFrame() call.  As soon as you hit a stopping frame you want to remove that listener.
If the modulus approach wouldn't cut it for all cases, then you could also try to work out some form variable implementation that is assigned the last stopping frame number as you move forward beyond it, using that variable to check against the currentFrame value in the ENTER_FRAME event handler function.