Honestly I have waited a lot before trying it, thinking it would be another pain in the ass time with the computer, and I got the OT to get away from the computer ah ah!
But it went quite like a breeze.
OT as a master, sending CCs for AUDIO TRACKS, and sending transport
Live as a slave
Set some MIDI tracks with long clips in the arrangement window
I did not touch anything to configure furthermore
I set a recording and tried the fader, found what parameter (CC48 I think) in the MIDI clip was then having an automation, and all was ready.
Press play with the OT triggers the ableton MIDI clip recording, then you play the song (I only use the fader this time),
and when it's done, just press play on the OT with ableton playing the MIDI clip and the OT's fader will (virtually) move.
I think I managed to have separate clips on separate ableton channels automating different OT's parameters but I think I had some trouble with it, conflicts somewhere, I'm more into the live set prepping and gigging these days than working studio-mode (and it now bores me to death to extract the live matter of the OT into a clinical DAW environment ah ah!)