Old topic, but I have the same problem.

I try in firefox and Chrome without success.

Firebug say:
topParentID is not defined
http://youdanz.com/gzip_loader.php?file=bx_templ_js_726eba7d64b286febf090b39d683697d.js
Line 850
and

missing ] after element list
http://youdanz.com/administration/menu_compose_admin.php
Line 810