This string is the piece of information that blocks out the middle cc number on the confirmation page to a row of x's. the one page checkout dosent seem to need it and the error is fixed when you remove it,
like this:
'field' => substr($this->cc_card_number, 0, 4) . str_repeat('X', (strlen($this->cc_card_number) - 8)) . substr($this->cc_card_number, -4)),
'field' => substr($this->cc_card_number, 0, 4),
however this does not fix the problem of the missing fields below. The table for the fields seems to be in the payment_method.php file in the checkout folder. I still dont know why it isnt showing.