Thanks for your post. I recently tried to set up something very similar. I'm attempting to play multiple instruments on different tracks by assigning different midi channels on those tracks as you suggest. I have a keyboard capable of sending midi out to up to 16 tracks (Korg M1). The idea is to swich the midi transmit channels in order to play the different tracks, sometimes multiple tracks at the same time. I'm using iConnectMIDI2+ interface and Logic X. I did verify that midi is being transmitted correctly from my keyboard (using midi monitor) and that Auto Demix it clicked on.
The thing that is a little different about my set up is that I want to trigger multiple tracks that are set to the same midi channel. In other words channel 1 might have an instance of Massive and another track on midi channel 1 with an instance of Alchemy. On channel 2, an instance of Kontakt and channel 3 an instance of Zebra. When I switch channels from my keyboard, only the first instance of the tracks that have the same midi channel plays. All the tracks are selected and record enabled. I tried using track stack folders but it still didn't work.
Any hints? I've been at this for some time so I've double and triple checked this. Set it up in brand new files to start clean etc...
• Logic version and sub-version (Logic 10.0.6)
• OS X version (OS 10.9.2)
• Computer (iMac, early 2013)
• Processor (i7)
• Memory (24 GB)
• Audio interface (Focusrite Scarlett 2i2)
• MIDI Controllers (iConnectMIDI2+, QuNexus, Korg M1 keyboards)