I just got a Keylab essential 88 (not MK2 or 3) and seem to be encountering lots of issues integrating it with Ableton Live 12 Suite (Windows 11) that appear to be commonly referenced but never resolved in this forum. Since this keyboard is old, many of the posts are also old and refer to old versions of Ableton.
My primary issue: When I simply select DAW on the board (Pad 2) the map sends non-note MIDI messages on higher keys that trigger other unexpected Ableton functions.
[EDITED] This issue appears to be created when I misconfigured the Ableton MIDI device Settings. I did resolved it… but don’t know exactly how yet. I initially selected Keylab Essential 88 for the Control Surface and used the Keylab Essential 88 (Port 2) options for both Input and Output (rather than the DAW option. Then for MIDI Input and Output Ports, I ticked the boxes for Track, Sync and Remote for the same Control Surface. But when I played specific notes on the keyboard - it triggered different functions in Ableton instead - such as note A6 appeared to trigger Undo and many notes above A6 triggered other non-note settings in Ableton. I believe when I deselected the Input and Output ports for Track/Sync and Remote - the issue stopped. I think.
I then reselected those options to see if I could duplicate the issue - but the notes continued to play correctly on the keyboard. I’ll keep trying to break it again and post my results here.