My Facebook app submit button is active upon loading, but as soon as I select a date/time, it fades and becomes inactive. I also have a PayPal button there that takes to a blank page when clicked. Anyone?

You cannot use PayPal with the Facebook app.
The ABPro app is displayed in Facebook via in iFrame. When the PayPal button is pushed it redirects the user to PayPal to pay. There is no way to redirect the user back to a Facebook app after payment.