“The mapping is complicated but I’m getting there. However, I’m stuck on the mute and solo functions, and on selecting tracks in the mixer. Does anyone have an idea? Thanks in advance. I’m mapping on a KeyLab Essential 49.”
What exactly is it, you want to control via your Keystep Essential? What do you want to mute or solo? Stacks or Layers? What‘s your intended workflow? And what does not work as expected?
You’ll find everything that can be remote controlled in Actions & Shortcuts. But I guess, you already know that. 
I’m preparing a concert set of about 10 songs and working with the mixer to make things easier. I can’t seem to get it to select a specific track to mute or solo.
My setup involves layers and their zones, plus two stacks: guitar and vocals.Everything works except that; if you have any ideas, thanks in advance. Christian Cardin
In your case I’d suggest to add Automation Tracks to solo and mute specific tracks, layers and/or stacks.
Simply route an Automation track to the desired object and then draw in the action of your choice in the Automation Editor in the Lower Zone.
Or do you need to select things spontaneously to mute/solo them?
I think I found it — there’s a “selected track” function, and from there you can choose solo or mute. Thanks for your help. Tomorrow I’ll redo everything so it’s nice and clean. It worked, my controller is just missing a few buttons. Thanks for your help. Christian