Paypal Auto-Return With Multiple Store Fronts?

How do I setup Paypal Auto-Return when using multiple storefronts?

Cs-cart Instructions say


But what do I use for when I have three stores with different domain names using same paypal account?

Our Paypal orders in Admin Panel all come back with a Status of Open (even if customer returns from Paypal to our site)?

CS-Cart 4.9.2.SP2