Preloader help!

ok, I’ve been using flash for a long time, but I’m still kinda new to advanced AS2. I am creating a photo album and I need to make a preloader. Basically what my album does is load about 12 full size photos at once, and displays them all as thumbnails on the side. There is a larger window that displays whichever one you click on in the thumb gallery. and by default on the opening it displays the first pic. I created this project for a friend hoping to learn how to do this completely in actionscript. Which so far I have done successfully. Now, I want to go in where I have the function that loads the pictures into the movie and add a preloader. This way when the page opens up, every photo displays a percentage of the loading picture.
Here is my actionscript:

var filePath:String = "pics/";
var clicks:Number = 0;
var picAmount:Number = 33;
var lastPage = picAmount-11;
function newClip(libName, instName, objWidth, objHeight, xpos, ypos) {
    attachMovie(libName, instName, getNextHighestDepth());
    this[instName]._width = objWidth;
    this[instName]._height = objHeight;
    this[instName]._x = xpos;
    this[instName]._y = ypos;
}
function fadeIn() {
    this.container._alpha = 0;
    _root.onEnterFrame = function() {
        container._alpha += 6;
        if (container._alpha>99) {
            container._alpha = 100;
            delete _root.onEnterFrame;
        }
    };
}
function newPic(contName, picNum, xpos, ypos, picWidth, picHeight, type) {
    var aNewPic = attachMovie("dummy", contName, this.getNextHighestDepth());
    var picNum = picNum;
    var fileName = filePath+"Picture"+picNum+".jpg";
    var my_mcl = new MovieClipLoader();
    var myListener = new Object();
    myListener.onLoadInit = function(target_mc) {
        target_mc._x = xpos;
        target_mc._y = ypos;
        target_mc._width = picWidth;
        target_mc._height = picHeight;
        if (type == 1) {
            target_mc.onRelease = function() {
                fadeIn();
                loadMovie(fileName, "container");
            };
        } else if (type == 2) {
            target_mc.onRollOver = function() {
                //trace(this+" onRollOver called");
            };
        }
    };
    my_mcl.addListener(myListener);
    my_mcl.loadClip(fileName, aNewPic);
}
function prevNext(instName:String, xpos:Number) {
    attachMovie("arrowMC", instName, getNextHighestDepth());
    this[instName]._x = xpos;
    this[instName]._y = 520;
    this[instName]._width = 18;
    this[instName]._height = 18;
}
function page(startNum) {
    var addNum:Number = startNum+12;
    var subNum:Number = startNum-12;
    newPic("thumb01", startNum, 60, 124, 45, 30, 1);
    newPic("thumb02", startNum+1, 111, 124, 45, 30, 1);
    newPic("thumb03", startNum+2, 60, 160, 45, 30, 1);
    newPic("thumb04", startNum+3, 111, 160, 45, 30, 1);
    newPic("thumb05", startNum+4, 60, 196, 45, 30, 1);
    newPic("thumb06", startNum+5, 111, 196, 45, 30, 1);
    newPic("thumb07", startNum+6, 60, 232, 45, 30, 1);
    newPic("thumb08", startNum+7, 111, 232, 45, 30, 1);
    newPic("thumb09", startNum+8, 60, 268, 45, 30, 1);
    newPic("thumb10", startNum+9, 111, 268, 45, 30, 1);
    newPic("thumb11", startNum+10, 60, 304, 45, 30, 1);
    newPic("thumb12", startNum+11, 111, 304, 45, 30, 1);
    newPic("thumb13", startNum+12, 60, 340, 45, 30, 1);
    newPic("thumb14", startNum+13, 111, 340, 45, 30, 1);
    newPic("thumb15", startNum+14, 60, 376, 45, 30, 1);
    newPic("thumb16", startNum+15, 111, 376, 45, 30, 1);
    newPic("thumb17", startNum+16, 60, 412, 45, 30, 1);
    newPic("thumb18", startNum+17, 111, 412, 45, 30, 1);
    newPic("thumb19", startNum+18, 60, 448, 45, 30, 1);
    newPic("thumb20", startNum+19, 111, 448, 45, 30, 1);
    newPic("container", startNum, 186, 150, 493, 331, 2);
    prevNext("nextButt", 195);
    this.nextButt.onRelease = function() {
        if (startNum>=lastPage) {
        } else {
            page(addNum);
        }
    };
    prevNext("prevButt", 100);
    this.prevButt.onRelease = function() {
        if (startNum<=1) {
        } else {
            page(subNum);
        }
    };
    this.prevButt._rotation = 180;
}
newClip("redMC", "red", 194, 629, 53, 0);
newClip("picAreaMC", "picArea", 542, 380, 166, 124);
newClip("LogoMC", "logo", 245, 72, 30, 30);
newClip("backButtMC", "back", 130, 59, 77, 533);
this.back.onRelease = function() {
    getURL("../index.html");
};
page(1);

I have searched all over the internet for answers to my problem, including preloader tutorials, and nothing covers exactly what I want to do. Please help.