the "live" version can be found here...
however, "buying" this item, you'll need to select from 2 drop-down lists, choose the first item(s) from both lists.
when you need to sign-in, to "buy" the item use this username and password
(I'll change the password after you've used it)
"tick: the T&Cs, select credit card, same billing address address (use UK mainland) from the drop down.
you'll see the Shipping on the confirmation page, it should be £4 but its £6
the shipping charge is generated from session (ShipCharge) which in turn is generated from a database look-up
this is the shipping rule:
if session variable exists: ShipCharge
create a flat rate shipping of $ $_SESSION['ShipCharge']
here's the database look-up
WHERE shipWEIGHT >= colname AND ship_rate.shipZONE = zZONE
ORDER BY shipZONE ASC , ship_rate.shipWEIGHT DESC
colname = $_SESSION['zoneWEIGHT']
zZONE = $_SESSION['zoneNUMBER']
the WEIGHT & NUMBER donate the combined product(s) weight and the number is a zone reference, different zones charge different amounts (mainly due to distance)