Not sure what you mean by 'can't change the value for yaw'? Did you mechanically balance the rig with the camera? Carry out all the advice in the manual. What board and software are you using?
I have the same basic problem. DYS Gyro, basecame board 1.0, firmware 2.0b4. Worked pretty good in plug and play mode. Tried to upgrade to more recent GUI software and firmware. tried to up grade using GUI, Tried using X-loader. Always failed and now plug and play doesn't work, camera seems to move randomly. I'm stumped, need help!