Qr Codes And Photo Credits

Hi Tim,
I am still looking into using QR codes for kinder photos.  I have set up a test gallery and the pre registration form that captures the child and parent data is great but I can't figure out how to smoothly make that work with the registration credit that parents register for before photo day. At the moment they pay and register ahead of time and that generates a credit in their account, but if I enable the pre registration for QR codes they enter their details there before they purchase the credit and that looks confusing to me (if I was a parent).  Is there an easy way to make that work?  

Thanks 

I can't think of a way for them to purchase a credit and also register for the QR gallery. They would have to do that separately.

I do have plans on being able to import data from Pre-Orders into QR Passcodes.