To get rid of it:
Open: inc/functions.php
Find: (Around line 1694)
PHP Code:
$template .= "<div style='position: fixed; bottom: 0; left: 0; color: white; font-size: 10px; width: 380px; '>A total of {$GLOBALS['numberofqueries']} queries were used in this page. They were: {$GLOBALS['queries']}</div>";
And completely delete that line. Problem solved.