Jay:
Now that I have been chastised for misunderstanding your post, though my tail is firmly planted between my legs, I thought I might offer an approach that I know works on channels less than 8 with my Turnigy 9x V2 transmitter.
I was working with a Hobby King HK-T6A-V2 6 channel receiver (I have also used the Turnigy 8x receiver), and the Lumifly Lighting system FAA Configurable (Lumifly-1) plugged into channel 5 on the receiver.
After binding my receiver to the Model definition I wanted to use my plane on, I followed the transmitter menu for "Func Settings" where I pressed the "Dn" key until I landed on "Aux-Ch". I selected this option by pressing the Menu key. The resulting screen landed me on Ch5, where I simply had to press the "+" and "-" keys until the "gear" option came up. I then clicked the "Menu" button again to save/select that choice. I then backed out of all the menus using the "Exit" key.
From that point forward, I have been able to get the lights (connected to my Lumifly board which is in turn plugged into the Ch5 port of the receiver, to turn ON, by simply flipping the switch on the upper right of my transmitter next to the Trainer switch. Forward is ON, switched back is OFF.
Hope that helps.
You should know that this Lumifly adapter board has 3 leads active in the cable to the receiver. Checking for 3 leads (rather than 2), which is all that some adapter boards use, is an easy way to distinguish the boards that interpret the digital signals that are sent on the white signal line of the cable and can control LED on/off functions from the transmitter. The 2 lead boards are just able to power the LEDs and usually flash them at preset intervals, but cannot control ON/OFF LED functions from the transmitter.
Cheers!
VJ