I am having the same problem. The payment is made but eShop doesn’t think so. I receive a failed IPN message from eShop. The header says “Paypal IPN -A Failed Payment Ref:”
I am using US Dollars in eShop as well as in my business account.
By the way, I love the plugin. It’s a little cryptic to figure out how to use it but I like the way it works once set up.