Never mind, I found it (right click on channel to open channel agents directory). As usual, it’s a shame that Eucon won’t follow it automatically. 
Although, based on the success I’ve had with programming layouts to follow configurations, I suspect that it MIGHT be a feature that could be programmed in.
I’m sure it wouldn’t be worth the hassle though, since you’d have to lose a blank layout for every configuration you build, in order to get back to regular mix status, not to mention how many scenarios you’d have to predict in order to cover that task! 
You only get 48 layouts on the Artist series (96 on the S6). So, your max count of fully functional setups would only be half that amount.
But at least you can program a shortcut button to access the channel expand from the MC Control. That’s something. 