Thank you for all the help so far... Ran into another question.
If I am adding several 'editable' fields in a dynamic cart button, can I store the main (productId, qty, price, orderId) in the order details table, and then store my registration fields (first, last, company, etc.) in a separate table? Or am I just making this more complicated than it needs to be....
lastly, would I add <?php echo ((isset($_POST["fieldname"]))?$_POST["fieldname"]:""); ?> in the bindings section for each editable field where I am accepting text or checkbox