Your page is with errors and some of the insertions of orverride and javascript seems not right.
At least, from the source, the address are wrong.
Code:
//--></script>
<script type="text/javascript" src="/includes/templates/jscript_header.js"></script>

<script language="JavaScript1.2" type="text/javascript" src="mm_css_menu.js"></script>
For time saving, instead of guessing and prevent errors from both sides.
If possible give the javascripts and related files. I will carry out the basic test in my side and give you the basic report.