Hi Jason. Many thanks again for your assistance. I have refunded the test transaction.
Hopefully this will be my final question. My client wants to display the GST (A 10% tax) in the cart and the email receipts etc. The GST is to be calculated on both the product and the shipping. I have been able to configure the cart to do this but ultimately do not want the GST to be added to the final cart total as it is already included in the existing product price and shipping. Therefore is there a way in which I can prevent the Grand Total from being updated with the GST tax.
Many thanks again in anticipation of your assistance.