This helpnote explains how to add the Mini Cart to a custom page.
Simply add the below code to your custom page:
<%option explicit%>
<%response.buffer=true%>
<!--#include file="shop$db.asp"-->
<%ShopOpenDatabase dbc%>
<table border="0" cellSpacing="0" cellPadding="0" width="140" style="border:1px solid #ccc;font:12px arial,sans-serif;padding:2px;">
<tr>
<td align="center" colspan="2" bgcolor="#CCCCCC" style="padding:3px;"><B>Cart Items</B></td>
</tr>
<tr>
<td>Qty</td>
<td><%=navigateproductquantity()%></td>
</tr>
<tr>
<td>Total</td>
<td><%=navigateproductTotal()%></td>
</tr>
</table>
<%option explicit%>
<%response.buffer=true%>
<!--#include file="shop$db.asp"-->
<%ShopOpenDatabase dbc%>