RobAc,
I have been playing with.. my crap still, and instead of radio buttons I am using a drop down value.. and I have ran into the same somewhat problem as you.
There is a Default Value = NA that it keeps going back to instead of the other 2. Like when I select it and save, it does it and when I view it in the member's profile it shows it but when I go back in to change something else, it will go back to default.
What I did to fix it, considering I have no clue why it won't take characters just numbers
I put default value as = -1 and the others are 1 and 2..
now it works... for some odd reason.
Anyone know if you have to have "A" or 'B' or just leave it as the character for it to work properly.