Change FTP password and Email-FTP-SSH access rights for default user on Virtual Server

The tutorial at http://www.virtualmin.com/documentation/tutorial/how-to-change-a-mailbox... doesn't seem to apply any more, or doesn't apply to the auto-created user for the domain.

I want the auto user to not have any Email-FTP-SSH rights (may delete that account),- How? There seems to be no way.

Can't click the checkbox and Modify Selected User.

and to change the password as we have had a personnel change. There seems no GUI way to do this either. Is there?

How is this done from the command line?

Thanks, K