MODx has a very powerful user management system. We will use this to restrict user commenting to registered, logged-in users.
The Group
Log in to your MODx Manager as an admin user with permissions to manage web users. Go to Users -> Web permissions.
Create a new web user group.
The Users
Now go to Users -> Manage web users, and create a new web user.
Give the user a username and a password (or let MODx generate a password), fill in the Full Name and Email fields; these are required. The Email address can't be used by any other user.
Finally, at the bottom of the New user form, check the box for the new group you just created.
You can have as many users as you like assigned to the group; you can also assign a user to as many groups as you like.
Configuring the Snippet
Now we need to finish up by configuring the UserComments snippet to only allow logged-in users assigned to our Web Group to see the comment form.
[!UserComments? &makefolder=`1` &canpost=`Blog Readers`!]
