I just configured your test portal to use authorize.net and the show paypal checkbox checked. When I tried to check out using the paypal options I get this error when I click on the paypal button

A critical error has occurred.
The stored procedure 'dbo.Smith_AddCustomer' doesn't exist.

I set it back because I didn't want to leave my auth.net api and key in there. This isn't the error I receive, but it still is an error. Please verify.