Ti faccio vedere l'HTML e tutto il js perché l'animazione non và :/

Codice PHP:
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN">
<html>
<head>
    <title>Home</title>
    <link rel="stylesheet" href="style.css" type="text/css" />
    <script type="text/javascript" src="mootools.svn.js"></script>
    <script type="text/javascript" src="slider-menu.js"></script>
    
</head>

<body>
    

<div id="slider_container">
    <ul id="slider">
        <li id="kwick_red" class="chapter"><span>Red</span>
        <li id="kwick_orange" class="chapter"><span>Orange</span>
        <li id="kwick_yellow" class="chapter"><span>Yellow</span>
        <li id="kwick_green" class="chapter"><span>Green</span>
        <li id="kwick_blue" class="chapter"><span>Blue</span>
        <!-- <li id="kwick_indigo" class="chapter"><span>Indigo</span>
        <li id="kwick_violet" class="chapter"><span>Violet</span> -->
    [/list]
    
</div>

    
    
</body>
</html> 


Codice PHP:
window.addEvent('domready', function(){

    var szNormal = 117, szSmall  = 100, szFull   = 219;
 
    var kwicks = $$("#slider .chapter");
    var fx = new Fx.Elements(kwicks, {wait: false, duration: 500, transition: Fx.Transitions.Back.easeOut});
    kwicks.each(function(kwick, i){
        kwick.setStyle('opacity',0.8);
    });
    kwicks.each(function(kwick, i) {
        kwick.addEvent("click", function(event){
            var container = $("#slider_container");
            var fx = new Fx.Tween(container, {wait: false, duration: 500, transition: Fx.Transitions.Bounce.easeOut});
            fx.start('height',300, 100);
        });
        
        kwick.addEvent("mouseenter", function(event) {
            var o = {};
            o[i] = {width: [kwick.getStyle("width").toInt(), szFull]}
            kwick.setStyle('opacity',1);
            kwicks.each(function(other, j) {
                if(i != j) {
                    var w = other.getStyle("width").toInt();
                    if(w != szSmall) o[j] = {width: [w, szSmall]};
                }
            });
            fx.start(o);
        });
        
        kwick.addEvent("mouseleave", function(event) {
            var o = {};
            kwicks.each(function(kwick, i) {
                o[i] = {width: [kwick.getStyle("width").toInt(), szNormal]}
                kwick.setStyle('opacity',0.8);
            });
            fx.start(o);
        });
        
    });
});