Now it's basically a caveat emptor. If you can't figure out the Keycode retrieval system at Prolific (who can?) then e-mail us.
On the Prolific site, even if you are logged in, you are offered in at least 2 places to Login, which is very confusing. When you are logged in, all offers to login should disappear and be replaced by a Logout link. And there is nothing about Serial numbers, Keycodes, Product Codes, etc. Only "Order History" which if you click randomly about eventually gives you a list of things you've ordered, but since 99L, 1.0, 1.1, and 2.0 are no longer products that Prolific sells, they simply show "Product Deleted".
I can understand why Prolific wanted to move to 1 system, but it needs to be the same level of ease of use that SereneScreen.com now enjoys.