This looks as though you are just doing the testing on your local machine. [$WAGLOBAL_Root_URL = "http://localhost/britannia/" ;]
What happens when you upload all to remote site and test there?
If your CMS files are in a folder called 'CMS' in the root directory on your remote (live) site, then the 'WA_Globals/WA_Globals.php' file for your remote website would be:
<?php
$WAGLOBAL_Root_URL = "http://www.yoursite.com/CMS/" ; //Absolute path to your site folder.
$WAGLOBAL_Site_Name = "Britannia Site Admin" ;
$WAGLOBAL_localRoot = "/CMS/"; //relative path to your PowerCMS files on your local testing server.
$WAGLOBAL_remoteRoot = "/CMS/"; //relative path to your PowerCMS files on your remote server.
//iRite Images upload settings
$WAGLOBAL_Images_Folder = "images/"; //relative path to your images folder.
$WAGLOBAL_Swf_Folder = "swf/"; //relative path to your swf folder.
// Admin Settings
$WAGLOBAL_Admin_UserName = "author" ;
$WAGLOBAL_Admin_Password = "britannia" ;
?>