So after using the test version of 5.2.5 for a bit, I decided to purchase the engine. I recieved my key, and downloaded V5. Then, when I try to build my game, it says I need to register the editor.
I go to the register editor window, and it keeps saying that my user name does not match the key.
I know I am typing the same key in that I got in the email, and I have tried typing my full name, and my user name associated with this site.
EDIT: The error says "Serial key for this username is invalid."