Just a little tip I couldnt find searching for it.
You can transfer your old Arma 2 key bindings to your new AO profile.
AO will see your old nick, but it wont change any settings...unless you:
1. Start Arrowhead to check if your old profile is there. If so, select it and quit the game.
2. Go to where your Arma 2 / AO profile keybindings are:
C:\Users\(Computer name)\Documents\ArmA 2 Other Profiles\Your Nick
C:\Users\(Computer name)\Documents\ArmA 2
3. Copy and paste the old Arma 2 key bindings into the same folder so you have two files there.
4. Copy the name of your AO profile file and then rename it something else.
5. Now rename the copied old Arma 2 key bindings to the AO name. Done...
You will get all your old key bindings and the new AO key bindings will be default.