First add this to Your sidepanel function,
// TOPUSERS fucntion call begin
$this->topusers();
// TOPUSERS fucntion call end
After the sidepanel function add this function.
// TOPUSERS Function --- Begin
function topusers()
{
$users=qa_db_single_select(qa_db_top_users_selectspec(0));
$newusersarray=( array_slice($users, 0, 10 ) );
$this->output('<DIV CLASS="qa-sidepanel-box-oben">');
$this->output('</DIV>');
$this->output('<DIV CLASS="sidepanel-box-two">');
$this->output('<h2>');
echo "Most active users";
$this->output('</h2>', '');
$this->output('<ul CLASS="qa-sidebar-user-ul">');
foreach ($newusersarray as $user)
{
$this->output('<li class="qa-sidebar-user-li-avatar">'.qa_get_user_avatar_html($user['flags'], $user['email'], $user['handle'],
$user['avatarblobid'], $user['avatarwidth'], $user['avatarheight'], qa_opt('avatar_users_size'), true).'</li>');
$this->output('<li class="qa-sidebar-user-li">'.qa_get_one_user_html($user['handle'], false).'<br />'.qa_get_points_title_html(($user['points']), qa_get_points_to_titles()).'
('.number_format($user['points']).')</li>');
}
echo "<li class=\"qa-sidebar-user-li-all\"><a class=\"qa-sidebar-user-link-all\" href=\"/users/\">All users</a></li>";
$this->output('</ul>', '');
$this->output('</DIV>');
$this->output('<DIV CLASS="qa-sidepanel-box-unten">');
$this->output('</DIV>');
}
// TOPUSERS Function --- END