If you are set on a 0 gain, then it's not going to move. I believe the DX6 has -100 to +100 on the gain, and if so, 0 is like there is no gyro at all. You need to set position 0 to about 45% which is where I start all gyros for the initial testing. Position 1, set to 0 so you have a way to check center, or you can set a negative number. And position 2, set to a rate mode setting. Use 2 to set teh drift in the air by adjusting the linkage rod for a perfect tail.
Sorry for the delay in replying, been quite busy here lately.