Block admin page stuck on admin theme

I have noticed a bug when using Advanced Forum.

If you set a theme for the admin section using the 'Administration theme' option, when you go to edit blocks it only loads the blocks for the administration theme, if you click on the separate themes to edit their blocks it still loads the default admin theme block list.

I have tracked this down and the error lies with the following code:

function advanced_forum_get_forum_theme_directory() {
  //TODO: Add a settings page for this
  return 'advforum';
}

My work around to fix the issue is this:

function advanced_forum_menu($may_cache) {
  $items = array();
  if ($may_cache) {
    global $user;
    $items[] = array(
               'path' => "forum/markasread",
               'title' => 'Helper page to mark forums read.',
               'callback' => 'advanced_forum_markasread',
               'access' => user_access('access content') && $user->uid,
               'type' => MENU_CALLBACK,
               );
  } else {
    if(arg(0) != 'admin') advanced_forum_add_css();
  }
  
  return $items;
}

I'm not quite sure if the best solution, but it works for me. If I used the below everything works except when viewing a forum post so using != 'admin' seemed the easiest work around.

 if(arg(0) = 'forum') advanced_forum_add_css();