Hey Fitzy,
First of al you need to bind your receiver to your transmitter. Also refer to the manual for this. The manual can be found
here.
In short:
Connect the bind plug to the "bat/bind" pins of the AR6200 en connect your ECS (with BEC) OR your UBEC to any one of the other channels. Then, first switch on the receiver (be sure to have the motor unplugged from the ESC). Then while holding the trainer switch in the on (up) position, swith on the transmitter. The Dx6i will show "Bind" in the screen. Wait for the light on the receiver to stop blinking.
Unplug both receiver and switch of transmitter, and that's that.
Oh, a quick remark. The receiver saves the all channel inputs while binding. In case of signal loss it will return to these settings! So don't bind with full throttle up!
Than to answer you question, And again refer to the manual. The manual can be found
here.
This is how to plug in the channels
aux1: (so called) pitch servo, one of the servo's that connects to either the right or left side of the swashplate
gear: Gyro gain (the plug with only one yellow wire)
rudd: Gyro (plug with three wires, usually white, red, black), plug the rudder servo into the gyro
elev: Elevator servo (tilts swashplate forward and backwards) (of course in CCPM at three servo's participate in swash movement, but you get the picture)
ail: Aileron servo, one of the servo's that connects to either the right or left side of the swashplate
throt: ESC
bat/bind: Only in use if you don't use the BEC of your ESC. In that case this is where the UBEC wire goes.
The pitch and aileron servo on the "aux1" and "ail" channels can be switched. You can adjust for this in the menu of the Dx6i.
Hope this helps.
Good luck with it!