Walkera g-3d 3 axis brushless gimbal

Hi , Again a gimbal question .
I followed all instructions i could find on gimbals to get i to work with my Pixhawk…no succes or i don’t really know how it should work.?!.
My config is this , I have connected the Roll (= AuxKB5 /CH10/RC10 of the devo F12E ) to output to Aux 10 on the pixhawk and Tilt (= AuxKB6 /CH11/RC11 of the TX ) to Servo 11 of the pixhawk.
When i choose the Passtrough of the channel all works fine i can control the roll and tilt, when i use CHxOpt = RC 10 or 11 all works fine and i can control the roll and tilt.
When however i configure the Pix to have a gimbal , in mission-planner …i cannot control it with the Devo F12E anymore …I use the settings in the ardupilot docs , http://ardupilot.org/copter/docs/common-camera-gimbal.html#common-camera-gimbal In RC Inputchannel i use the RC10&11 .

What am i doing wrong ?..