Script Modification - 11/12/2008

I want to modify my website the following way: 1. I want the user URL inside their own folders. For example, instead of [login to view URL] I want it as [login to view URL] 2. I have a few users that registered using user names such as "Raull Makintare" and "johna.rodriguez" the script does not support space in the username and does not support commas, period, or any other chracter. Only letter and numbers. Please created a way that users get an error if they try to register using none supporting usernames. I will send details of my website to the winner.