$_GET['Login_ClientID'] is not the correct variable to use. the ID is not saved to a get variable, it is saved to a Session Variable. assuming that Login_ClientID is the name of the session created by the login behavior, the run time value to use in the recordset is:
$_SESSION['Login_ClientID']
and you may need to add:
<?php @session_start(); ?>
at line 1 of the page.