Dragging chord diagram to custom palette not working on Yosemite

I'm running v 2.0.2 on Yosemite 10.10.5
I've created a custom workspace and custome palette in it to store my own guitar chord diagrams.
I cannot find a way of dragging a new chord diagram from the score to the new palette - manual says CTRL+SHIFT - I've tried every combination of CTRL, CMD, ALT, SHIFT and although the chord symbol drags across to the custom palette, I get no + sign and nothing is saved in the new palette.

Any suggestions please?