Can't get Operation arrowhead to show?

[Enpi 15]

Hello! I have launched both ArmA 2 and OA and I still don't have the option to run Operation arrowhead even if I run as a Adim. I Can play DayZ but I want Operation arrowhead so I can use all the weapons/vehicle in the editor for my cutscenes.

Cheers!

[Enpi 15]

Anyone?