This addon is a plugin. You need to extract it to your /plugins folder to install it.
Adds required First Name and Last Name fields for users and allows them to be displayed in place of usernames
A simple plugin that adds two required fields to the registration form for First Name and Last Name and displays them in the basic info box on the user's profile. Users and Admins can edit these fields via the Edit My Account link on the profile.
To enable displaying a user's First and Last Name in place of their username on posts, go to Dashboard -> Forum -> FirstLastNames and click "Use Display Names".
1.3 - User links no longer blank If display names are enabled and a user hasn't set their first/last/nick name, will display their real username instead - If display names are enabled, clicking on the @username link on posts will now insert a mention into the comment box
1.2 - All the plugin's config options can now be set in the dashboard - Added some additional config options
1.1 - Fixed redirect bug with registration - Added ability for users and admins to edit names - Added support for a config option to enabled displaying first and last names on posts