2
That's a great tutorial, and it has helped me a lot in the past. The problem is that it's geared towards a previous version of XOOPS, so some parts of it don't apply.
If you want to cover a broad, but not comprehensive set of options for your site's users, go into your site's admin section. Click your mouse on "Users" and then on "Groups." You'll be able to control a lot of the permissions for your groups there.