Flaperons are already in the 14MZ. They are called 'camber', and are adjusted by the camber mix in the Model menu. When you have an airplane selected, you can go into the virtual channels in the AFR menu and see one marked as "camber". Set its control in the function menu to the one you want, adjust the camber mix, and you're ready to go. It's on page 89 of the manual.