I'm not sure I understand, are you having a problem running the wizard? or is the problem with the pages that the wizard generated?
The last page of the checkout wizard is to name the pages that are to be created.
are you saying that you cannot click on the checkout button on the confirm page?
API credentials are used by paypal checkout. the .pem file is used by Authorize.net.
Can you clarify what payment gateway you are using?
Which server behavior do you want to edit?