What version are you using? There is an Instrument Summary tool at the bottom of the spotlight tool palette in 2014. It collects everything you have used to build the Key. I often bypass the popup for entering info and just 'drop' the Key on the drawing. Then ungrouping and modifying it (by hand, sts) allows fine tuning it. I generally want it to be pretty minimal. It may have been over in the border controls before '14 - orrr up in the spotlight dropdown menu? Anyone?
I think I posted a file on the VW forum with a worksheet for this. The newish images in worksheets function can give you an updating legend with counts.