AbleCommerce Shopping Cart Software

After adding items to the cart and proceeding to checkout, the shipping methods aren't displayed until you continue the checkout to display the shipping method choices and credit card payment options. If I then continue shopping and add an additional item, the basket still has a shipping method assigned to it.

But if I now go back to Checkout, the shipping method has been removed from the shipment. Is there any way to have a default shipping method assigned when the user comes back to the checkout? Can I just change the page load event trigger the Continue button click so that the initial shipment choices will be selected?

If you are sure that some specific shipping method will be applicable always on shipment then you can try to select it. In fact when basket items are changed then there could be chances that some shipping methods are no longer available for example depending upon minimum purchase etc.

Our tiered shipping charges are based on the total order amount. We just offer Standard and Express. Standard is always available.

To do this, would I just need to work with the OnePageCheckout page?

Yes I think so, you need to set it on available methods list in OnePageCheckout control.