Just checking my paypal profile, good job I did as I hadn’t changed the reture url from when I moved the site a few months ago 
but the setting Payment Data Transfer (optional)
Do I need this on or off ?
If on then details of the payment is shown when they redirect back to your site
JOhn
So that's a good thing ? and it's best on then ?
I understand it sends back data, just didn't know is cscart used that data. I know my old shopping cart used to because it used to track part refunds etc and show them in the admin reports.