First of all, sorry to hear that you have problems getting the purchase and download completed. I can assure you that we will do what we can to fix it, and that we to date have been able to resolve all such situations satisfactorily
We have seen this problem before, and our download provider is working with PayPal to sort it out.
In the meantime, as long as you have received your PayPal order and invoice, you can consider the order is valid. I don't have access to the transaction systems and therefore can't look into what has happened with your order, but someone who has will be along shortly to help you.