User Manager can edit other user profiles

Hi!!
I have a question. I tried to solve by myself but nothing..
So.
I should create an user (that has backend access) able to edit and other users profile, to change name and other informations
so I created for him a Joomla Group named GROUP-A
Other users belong to group GROUP-B.
Users in GROUP-A are not Super Admin neither administrators.
They inherit by Public group. After this, I created an ACL named ACL-A and included the group GROUP-A
In CB users Management I set permissions for GROUP-A to create, delete, edit, and access to Administrative Interface
In CB Options I set Moderator Access Level to ACL-A.
Well, If users of GROUP-A try to edit an user of GROUP-B, a message says : You cannot edit a 'GROUP-B' user. Only users with a elevated privilege can do this.
Sorry for my english, I have CB in Italian so I traslated this message

What is the correct procedure to give to an user the rights to modify profiles of other users?? (Not admins obviously)
Thanks
Alberto

They inherit by Public group.

I do not recommend doing this. Public has no inherit permissions. This means you have to configure all permissions from the ground up starting in Joomla. I suggest making your usergroup a child group of Administrator which already has administrator login permissions and interface access then adjust permissions to from there for an easier configuration. The alternative has make your new usergroups child groups of Registered then give them additional permissions and you will need to start with Joomla permissions in Joomla global configuration so they can login to backend. CB has a check to prevent a user from editing a user with permissions higher than them and is what you're running into with your current setup.