Okay I don’t think my error was the same thing that the other user was experiencing.
I have enabled IPN but the only way the sale shows up in the sales section is if the user explicitly clicks the orange “return to [site]” button at the end of the paypal checkout process, this redirect the user to the home page. If the user does not click this button and just exits out the order will not be processed by the image store. I think that this is definitely an unnecessary step. Why doesn’t the plugin add the order when it takes the user to paypal to pay and then update the payment status on the redirect?
One thing to note is that even though the IPN URL is set to http://www.mysite.com/, when I look at the IPN log in paypal for a transaction the notification URL is set to http://www.mysit.com/galleries/%5Bgallery-name%5D/shopping-cart