The two skills that occupy the ground slot seem to work alright, in particular I can retrain them as their appropriate rank (Lt. for the top; Lt. Commander for the bottom). Problems arise when I try to retrain the one that is sitting in the actual Lt. Commander (which seems to be a Commander rank ability). It says "Replaces Unknown Node" and I'm unable to retrain that ability.
As I've said, I've had this boff since launch and I'm loathe to replace her. Two weeks with a GM ticket and all I got in reply was "submit a bug report". So here I am.