1) UTeam adjusts team names based on what access group a user in ULib is.
Teamnames have nothing to do with access levels. I could create a teamname called Superadmin in UTeam, but assign it to group 'user' and the person would join with no access. (A fun trick now that I think of it though, eh?)
2) ULX creates groups, and is used to assign people to those groups.
Each group can have different access to different commands. ULib (ULX relies on ULib) has 4 default groups - superadmin, admin, operator, user.
All people who join a server, if they have not been given a higher access by the server superadmins, start at group 'user'.
So, before your UTeam can work, you need to create new groups called the new ones you want.
ulx addgroup "superadmin1"
ulx addgroup "superadmin2"....
Did you not read the 'ulx usermanagementhelp' ... I recommend reading it again. It explains more.
Once you've used ULX to create the groups, you can edit the data\ULib\groups.txt after backing it up to 'add' or 'deny' any access you want the new groups to have. Though you _can_ use the "ulx groupallow" or "ulx groupdeny" commands to add one or two permissions to each group, adding more than a few would take a while and might be better done through the groups.txt file.