I did a complex Python script to fully integrate it into Ableton Live:
The tricky part is, that you need to send a “keep-alive” message every second to keep it turned on. Without sending this command every second, the CC121 is in idle mode with be blue Cubase Ready LED flashing.
This midi message is a system common message [0xF0, 0x43, 0x10, 0x3E, 0x15, 0x00, 0x01, 0xF7]
I think every 2s should be fine too.