I purchased a registration code online, but it doesn't work in the trial version?
Make sure that the trial version of the game was downloaded from the same website that you purchased the registration code from. A registration code will only unlock the full version of the game it was purchased for.
If you are still having trouble, please contact the support department of the website you purchased the registration code from. You should include your name, the purchase ID (if you have it) and roughly when you think you purchased the registration code in the description field - so they can locate your records.