Oh… trying to share a Push 2 with Ableton running probably won’t work, you’re right, because Ableton has the Push display open, and that’s not something that can be shared like a MIDI port can. I don’t think Ableton has really thought about trying to allow user mode applications to directly write to the display.
When I was testing Push in Max was back before the Push 2 had come out, and was without Ableton Live in any case.
As for libmapper, I don’t know anything about it, I am afraid!
Ah ok my bad. Tho I'm fairly sure I saw a (paid) lib and M4L projects using it that could share the screen and temporarily take over with like basically the clip note view ableton fomally implemented in live10