Ah...this is the answer....From Terry Howald @ Kessler Crane Support
Yes markers can be moved or deleted just like key frames can be moved or deleted, and in the same manner. So a tap and hold or right mouse click will launch the marker editing menu. Also, just like key frames, you have to disable the lock on key frames and handles in the Graph Options menu before you can edit markers.
It worked for me, but...there were three that I could not remove for some reason until after I restarted the brain & App. Go figure...