Find the menu, and next find section with shop menu, then replace it with:
PHP:
<?PHP
if($config['site']['shop_system'] == 1)
{
echo '<li>Shop</li>';
echo '<ul id="sub">
<li><a href="?subtopic=buypoints">Buy Points</a></li>
<li><a href="?subtopic=shopsystem">Shop Offer</a></li>';
if($logged)
{
echo '<li><a href="?subtopic=shopsystem&action=show_history">Shop History</a></li>';
}
echo '</ul>';
}
?>