If you will always also have your Push connected, I suppose you could also:
1) Use MT Pro to re-route your push to a virtual port and tell Ableton Live to look at that port for your Push instead of the actual hardware port.
2) Using MT Pro, re-route a button of your APC40 to the virtual port of your Push to send the same MIDI message that the push sends.
Essentially you would have
1) APC40MKII routed by default to BMT 1 - Define this port in Ableton Live your top section
2) Push routed by default to BMT 2 - Define this port in Ableton Live in your top section
In MT Pro route everything from and to APC40 to BMT1 using the MIDI router
In MT Pro route everything from and to Push to BMT1 using the MIDI router
Create a translator to take a button on your APC40 and convert it to the Push MIDI message, send this to BMT2 instead of BMT1 with swallow set.
Now again this will only work if your Push is also present. If you want to do this without Push present, there will need to be another translator in MT Pro to respond with the correct device inquiry Sys Ex response that the push sends (to fake a push present) and then ignore all other MIDI messages to and from Ableton Live to BMT2.
So this is the way to do it without having to modify any MIDI remote scripts. I looked at the Push MIDI Remote Script and my eyes glazed over. It would take me hours, maybe days, to figure out how to integrate this functionality into the APC40MKII MIDI remote script.
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