Hi,
You need to edit templates/default/header.tpl
ADD:
<a href="/forum/chat/flashchat.php">Chatroom</a>
// ABOVE:
{if $user_list}
<a href="{$config.BASE_URL}/ubbthreads.php{$var_start}ubb{$var_eq}showmembers">{$lang.USER_LIST}</a>
{/if}
This should then give you a link at the top.