Comments by Yalopa

1/ the max device should recieve MIDI, you can do this by arming the track or by setting the monitoring to "IN" on the midid track
2/ the "in control" checkbox of the M4L device should be marked

Hope this helps.
When I re-open a set, the plugin forgot the sound preset selected, and defaults back to the base setting (TB Lead01 I believe). A pity because, this plugin was exactly what I was looking for.