To be clear, you are using the alternative header version 1.1a and not Clyde's 2.0.
There is indeed a bug in it, as well as a PHP short tag (not recommended).
I recommend going to the tpl_header.php file and replacing this code
PHP Code:
<?
//<!--bof-drop down menu display-->
// <?php require($template->get_template_dir('tpl_drop_menu.php',DIR_WS_TEMPLATE, $current_page_base,'common'). '/tpl_drop_menu.php');?>
// <!--eof-drop down menu display-->
?>
with this
PHP Code:
<!--bof-drop down menu display-->
<?php // require($template->get_template_dir('tpl_drop_menu.php',DIR_WS_TEMPLATE, $current_page_base,'common'). '/tpl_drop_menu.php');?>
<!--eof-drop down menu display-->