i have a wordpress site and i am trying to add a phpbb3 forum system

the two work great alone, i was able to setup the WP phpBB Bridge (im not sure if it works or what it is supose to do), but when i try to set up the PHPBB Single Sign On which (to my knowlage) should combine the wordpress & phpbb3` users i encounter some difficulties.

the path, auth and patches are “OK” but when i try to do the common.php step the site stops working.

this is what it says to do:

It seems that this file is the original common.php file.
you will have to rename this file from common.php to common-orig.php
the file is in the folder C:\wamp\www\sys\forum

This file must be copied from C:\wamp\www\sys\wp-content\plugins\phpbb-single-sign-on\files\common.php to C:\wamp\www\sys\forum/common.php

any ideas on what could be the problem?

thank you