marketpress parallel payments. There was a problem finalizing your ...

Hi there
I have a global cart set up. when I add an item from just one store (either store 1 or store 2) the purchase goes through ok.

When I try and order one item from store 1 and one item from store 2 I get as far as paypal, then back to confirm order, then I click on confirm order and get the message.

"There was a problem finalizing your purchase with PayPal. Please go back and try again."

the thing is when I look at the paypal account I used to buy the itms, it has taken out the price of the first of the two items plus shipping for both of the items?. It hasnt taken the price of the second item.

No confirmation emails are sent out either