About "Direct Return" it is written here to choose "Header Redirect" (3. Under Direct Return select Header Redirect.) https://www.2checkout.com/shopping-cart/ubercart/
But it is written here to choose "Given links back to my website" (3. Under Direct Return select Given links back to my website.) http://www.ubercart.org/forum/support/31330/configure_2checkout_payment_ubercart_drupal_6
Do you know if given links back to my website is definitively the option to select?
More info about "How Does The Return Process Work?" 2checkout.com/blog/knowledge-base/merchants/tech-support/passbacks-and-returns/how-does-the-return-process-work/?plain