This is all is not working here. "M" does not insert a marker.
In my preference "M" is bound to the "global move tool".
Even if I unbind this shortcut "M" is again bound to the global move tool when I restart Sonar.
I have testet to exclude and include the shortcuts from the lenses, I have saved a lense with the unbounded "M" shortcut. Nothing helps. After a restart and several tests "M" is always bounded to the "global move tool".
And we have this problem on 3 computers. And it is not possible to bind any shorcut to insert a marker.