Ok, In /themes/zone99_xxxx/index.template.php look for:
if ($context['allow_calendar'])
echo '<li><a' , $current_action=='calendar' ? ' class="active"' : '' , ' href="', $scripturl, '?action=calendar">' , $txt['calendar24'] , '</a></li>';
After it add:
// SMFShop
echo '<li><a' , $current_action=='shop' ? ' class="current"' : '' , ' href="', $scripturl, '?action=shop"><span>Points</span></a></li>';
Change the word points to whatever you want.