Thanks for your quick response. Essentially it looks like every one is happy except the buyer - he does not get his digital product! Paypal gets paid, I get paid but the site does not go to the download page for the buyer to get the digital product.
I did go through the Create a Download Center, Create an Order History Page and Apply register/login to your Checkout Process.
Site not going to login from checkout. As I understand the flow shopper adds digital product to site, then goes to checkout where prompted to login. My site does not do that. Skips login and digital delivery but takes the money. Cool for me but not so much for client.
I do see that product I ordered has been entered in the orderdetails and orders tables. Also see Ray has been entered in the users table but my information as user has not.
UPDATE MONDAY MORNING
As of Friday my site, http://diybyphill.com, was going to Paypal skipping registration.php. So went back to tutorial on Apply registration/Login to Checkout Pages, Add Access Rules.
Tutorial says to open Security > Manage Site Access > Access Pages Manager. Then Grant Access If menu tutorial says choose Logged in to users, my only choice seemed to be Logged in to pcms2_users.
Tutorial says choose the If access denied, go to field browse icon. Tutorial says choose the Login page but graphic shows /users_Login.php in the If access denied field. Using /users_login.php and adding the ?checkout=1 seems to work best.
Even though the tutorial says to apply to all pages but cart.php I have found that if I delete the Server Behavior require_once( "webassist/security_assist/helper_php.php" ) from product.php the site goes on to cart.php. When I click on Checkout get 404 error and url says http://diybyphill.com/user_login.php?checkout=1&accesscheck=%2Fcheckout.php%3F. I deleted the Server Behavior require_once( "webassist/security_assist/helper_php.php" ) from user_login.php and checkout.php but the site does not go to registration.php which I understand is the next page in the flow. Nor does it go to Paypal as it did once before. Thanking you for your great help.