WordPress MU

I have put WPMU Blog Registrations by Aaron Edwards in my mu-plugins dir, and Register-Plus in my plugins dir (and only activated it for my sub-blog).

In My custom plugin, I have created script that adds roles and capabilities. It looks something like this:

if(!get_role('mngBall'))
      {
        add_role('mngBall',__('Manage Ball));
        $role = get_role('mngBall');
        $role->add_cap('mngBall');
      }

      if(!get_role('mngBrick'))
      {
        add_role('mngBrick',__('Manage Brick'));
        $role = get_role('mngBrick');
        $role->add_cap('mngBrick');
      }

By default, all users registering for my sub-blog, is assigned the role "newUser". This is set in blogs->edit area.

Using Register Plus, I've added some extra fields. One of them being a dropdown where the user can select their "role".

So, in order to automatically change this role to the selected role, I've added this hook:

function changeUserRole($userID)
{
$user = new WP_User( $userID );
$roles = array("role1"=>"role name 1", "role2"=>"role name 2");

// Set new user role.
foreach($roles as $role => $name) {
if( $_POST['role'] == $name) {
$user->add_cap($role);
$user->remove_cap('newUser');
}
}
}

add_action ( 'user_register', 'changeUserRole' );

Q1.
When I access the backend of a sub-blog, I can delete a user, and the user is removed from that blog.

But the user still remains on my main blog, and thus not deleted.
Why isn't the user completely deleted? How can I make sure that a user i completely deleted when I delete the user from a sub-blog?

Q2.
When I'm on blog3.myMainSite.com/wp-admin/wpmu-users.php, why do I see users registered for blog 1 and 2? Shouldn't I only see users registered for blog 3?

Q3.
If I have Register Plus activated, I'm not able to update user information when I'm on:
http://mysite.no/wp-admin/user-edit.php?user_id=11&wp_http_referer=%2Fwp-admin%2Fwpmu-users.php

I get the following error message: You can’t give users that role.
(I'm logged in as Administrator)

Register Plus also does not save additional WPMU info like Primary Site

Has onyone else experienced similar problems?