Magento – How to customize magento onepage checkout form

This problem is solved. The review part of the checkout is submited by the save function in skin/frontend/base/default/js/opcheckout.js around line 820.

This function does not take all fields into account from the agreements.phtml, but only the ones inside $('ol#checkout-agreements') - go figure...

The solution is obviously to to put the field inside the ul#checkout-agreements or to change opcheckout.js to include all the fields from the agreements.phtml.

Have you checked out the Config.xml in Sales/etc, and looked at the "sales_copy_order_billing_address" sections.

This defines which column gets copied over from table1 to "mapped columns" in table2.

So, add County to the list, wherever the data gets copied over for Shipping Address, and Billing address.

That XML mapping gets used when code like the following, gets executed:

Mage::helper('core')->copyFieldset('customer_address', 'to_quote_address', $address, $this);

The first parameter is the "from table column" node mapping, and the second parameter is the "to table column" mapping.

Hope this works.