jw,
Just to be clear..
The EasyTouch has three modes.. Pool, Spa, and Spillway. The Pool and Spa modes work right out of the box. The Spillway mode will not work unless someone sets it up.
If your Aux 3 Circuit has a Circuit function of "Generic" then it could not have been used to turn on the "Spillway mode". It has to be doing something else.. Tell me what the Aux 3 button does when you push it. Does it turn a valve or just make the pump change speeds or???
In any case, your Return valve is currently set to 50% spa and 50% pool. It needs to be set 100% spa off when in the Pool mode and 100% Pool off when in the Spa mode.
Then we can set up the actual "Spillway Mode" using a Feature circuit. When the Spillway mode turns on, the Intake valve will turn to suck water from the Pool and the Return valve will move to return all the water to the Spa. Instant spillover. You most likely will need to set a pump speed for "Spillway" to match the amount of spillover you want.
Thanks,
Jim R.