RE: GWS receiver on low channels
Using channel 16 is not a problem - the reason for the warning is that channels 11 thru 15 can get interference from channels 56-60 in the single conversion receiver.
Some things to check:
Is the transmitter set to PPM/FM and not PCM.
Futaba servo wiring is Black for - , Red for + , and White for signal. Same for battery less the white wire (if battery has a third wire, it is unused).
Plugs should go into receiver so they are all inline, not turned sideways so they are in two vertical stacks.
Does the GWS receiver have the F sticker to indicate it is for futaba?
Are you using the synthesized module on the 9C? I don't recall right now, but one of their synthesized modules is not compatible with non-futaba single conversion receivers.