Checkoutcomplete page for analytics tracking

I'd like to easily track completed orders in analytics tools. I see that the newer version of kartris no longer displays last URL as checkoutcomplete.aspx, instead it all show as checkout.aspx and uses server.transfer to load inner page within the page. Why was this done? and how would you suggest defining complete order page when checkout.aspx can be one of 4 steps in the order process (login & basket/shipping/billing/confirmation) - how can I differentiate to track between all these steps if they are all under one URL?

Please advise,

Thanks for any assistance,

<script>
<%
If mvwCheckout.ActiveViewIndex = 0 Then
%>
window.location.hash = 'login';
<%
ElseIf mvwCheckout.ActiveViewIndex = 1 Then
%>
window.location.hash = 'step1';
<%
ElseIf mvwCheckout.ActiveViewIndex = 2 Then
%>
window.location.hash = 'step2';
<%
End If
%>
</script>