OK, in your navbar template find
<td class="vbmenu_control"><a href="calendar.php$session[sessionurl_q]">$vbphrase[calendar]</a></td>
After it add
<td id="rpg" class="vbmenu_control"><a href="$show[nojs_link]#rpg">RPG Menu</a> <script type="text/javascript"> vbmenu_register("rpg"); </script></td>
Find
<if condition="$show['popups']">
<!-- NAVBAR POPUP MENUS -->
Below add
<!-- rpg menu -->
<div class="vbmenu_popup" id="rpg_menu" style="display:none">
<table cellpadding="4" cellspacing="1" border="0">
<tr><td class="thead">title</td></tr>
<tr><td class="vbmenu_option"><a href="option link">option name</a></td></tr>
</table>
</div>
<!-- / rpg menu -->
Repeat the title line to add additional titles anywhere in the menu.
Repeat the Option line to add additional links anywhere in the menu.
Make sure all additional lines go above </table>