cesarcesar,
I am unfamiliar with this app, and don't quite have time nor resources to fully test it, however you can check your PHP configuration if you are displaying errors!
Or, at the first line of the file you are accessing (under <?php) place:
<?php
ini_set('display_errors',1);
display_errors(E_ALL);
// ... file continues
A white screen with no data exported can mean you arent displaying errors, but there is a fatal error.
You can also look @ the PHP logs if you have access to them to see what is happening.