Spektrum Mixing / Programming ... ARGH!!!

[mclarkson]

I've started threads in the past, here and elsewhere, hoping to find someone who can explain the vagaries of Spektrum programming. These usually elicit several responses of, "I'd like to know that too!"

Followed by a few pointers to example set-ups which may work but never explain why / how they work.

Followed by silence.

Followed by me giving up.

Can it really be this hard?

Example from tonite. I need to use my AUX2 switch on the DX7 Tx to drive the gear channel. For whatever reasons, I need the switch to move the gear channel from -50% to +50%.

I try a setup. It doesn't quite work. But when I go back to programming, the Tx will no longer let me edit some values. I can edit them when I first create the mix, but never afterwards.

Let's say I start on MIX 1 with:
RATE: 50%
50%
OFFSET: -100

Let's say that doesn't work. I want to change the rates to 75% and 75%. Guess what? I can't.

When setting up the mix for the first time, I can flip the AUX2 switch up and down to switch between the two RATE settings in the mix. But, once I've set it up and tested it, flipping the switch does nothing. At all. I can never, ever get to the second rate setting.
RATE: 50%
(UNCHANGEABLE) 50%
OFFSET: -100


I have to start a new mix (MIX 2). When I set up this mix, I can flip the AUX2 switch up and down to enter values for the two rates but again, once I move off the Mix programming screen, I can never ever alter the second rate again.

So I have to start a new mix (MIX 3).

Etc.

Etc.

Until I'm out of mixes. If I go back to an old mix (eg MIX 1) I have to individually clear out ALL of the settings before it will let me alter the second rate again.

Am I missing something? Cuz I'm really frustrated.