I really cannot understand how they can ban you, of all people. I mean, you have always been polite, reserved, and very considerate of others ... especially when posting on internet forums.
Have you tried writing to them and asking specifically what and where the violation occurred ? I know you have many published examples of your fine writing technique -- Use your skills -- let them know exactly how you feel and what you think they should do. I am sure they will respond, and even if you don't get the ban lifted, the forum admin will know who you are and what you stand for.
Use your people skills