I did not have IPN notifications enabled at PayPal, so that was probably the problem. As I understand you message successful transactions occurred when users returned to the website after completing the transaction at PayPal and the transactions of users who did not return were not completed. I have configured IPN notifications so this should solve the issue, if not I'll have a look at the IPN log at PayPal and see what is going on.
Thanks for your assistance, it is tricky sorting through the PayPal set up even with your detailed manual as PayPal has changed the business configuration page and things don't match up very well. The Instant Payment Notifications setting is there plain as day and I should have caught it, so that is my fault. Thanks again for your help.
Richard Brundage