Paypal issues

I've built the following site: http://westernexporter.us/cart/index.php?view=home

When I perform a checkout it passes the data to paypal but when the paypal transaction completes it fails to send the customer back to the site and complete the transaction. You still get paid but the customer's cart stays full and your sale log doesn't update. Anyone have this problem? Any solutions?

I love the system. I hope there are more updates in the future.