your page is misising the menu script tag.
add the following just after the closing </ul> tag of the menu:
<script type="text/javascript">if(window.attachEvent) { window.attachEvent("onload", function() { cssmw.intializeMenu('cssmw1',{select_current: 0, orientation: 1}); }); } else if(window.addEventListener) { window.addEventListener("load", function() { cssmw.intializeMenu('cssmw1',{select_current: 0, orientation: 1}); }, true); }</script>
yes, on setting the width of 320px that would apply to each button. not the entire width of the menu.