courteneyfish: If you fill in your contact details it should default to the flag for that address.
Fairly certain that can no longer be done since April 1st of 2014. You now need to go through the verification process to be able to change your flag. At least I remember Icon stating that last year. As for the original flag, I know that when I started, you only received the flag after you chose whatever country one wished, when filling out info about one's age and origin (required before one could enter their 1st WGT tournament). Although I think that changed in time and people now get their flag automatically assignes, each according to their IP adress.