The tutorial for preloading in websites

i have all the code in the tutorial but can’t seem to get it to work on my own project. i looked it over a thousand times and understand what most of it is doing but for some reason it just sticks on the transition and when i click my buttons nothing happens. also does anyone know how i would switch it around to make the transition movie a “loading bar w/ percentage” type of transition?

heres the tutorial i’m talking about
http://www.kirupa.com/developer/mx/preloader_transition.htm