Have a progress preloader problem

here is the script that i am using.

myMCL.loadClip("load.swf", 50);
var myMCL:MovieClipLoader = new MovieClipLoader();
var myListener:Object = new Object();
myListener.onLoadProgress = function(target_mc, loadedBytes, totalBytes){
 _level50._visible = true
 var preloadPercent:Number =Math.round((loadedBytes / totalBytes) * 100);
myListener.onLoadComplete = function (target_mc){
 _level50._visible = false;

i have attached the prelaoder. i am wondering what i am doing wrong, because it is not working. could someone make a new fla file drop a pic into it, an then apply this script to see where i am makeing the mistake.

the purpose of this script is that it will load this particular image instead of numbers to display downloaded progress. if this doesnt make sence please ask.

thank you all in advance.