Sadly its still not working, I keep getting "Promotional key is incorrect, please verify code again" does it have to be in all caps, or will lowercase work?
I had the same problem, I copied and pasted the code directly from the website and removed the spaces; that actually was my problem. The form only accepts 20 characters and if you copy/paste directly from the page including spaces it truncates the last 4 digits. Just manually type them or copy only the 4 digits at a time.
Also if you're having trouble just entering the code from the game box to get your FFXVI code then it should be noted that the 0 and O need to be played around with a little bit. On the screen "font presentation" it shows the 0 with a strikethrough, this is not actually the case on the code - the 0 (zero) looks more like an O (letter) and the letter O looked like it was a misprinted and closed U. Just try changing the ones you have as an O (letter) to a zero and the ones that you have as a zero to an O and that might do the trick.
Kyansaroo - Kujata
Windurst Rank 10
BLM 75 / WHM 75 / BST 75 / RDM 75 / BRD 75
Next to 75: COR 47 / SCH 58