" it needs the faciltiy for users to change their forum username as currently each forum user is given their surname as their forum username and that cannot be changed by the user or the forum admin."
You can use the login name mod to phpbb found here: http://www.phpbbhacks.com/viewhack.php?id=1455
I just got it to work, and it allows you to have a login name (which is the surname) but it also lets you have a username, which is the name that shows up in the forums. You have to integrate it into the account edit, and create account files in OSC but it's not difficult at all. In the end, it makes this Forum contribution complete and just what OSC needs.