Harmony Premium - "Create Drawing from Drawing Selection" (Command 8) Not Working

Intermittent problem in which I use cutter tool to select a piece of a drawing and want to create a new drawing layer containing just that piece.

I am in the habit of pressing Command 8 on my Mac to “Create Drawing from Drawing Selection,” however that’s not working, and when I go into the edit menu, the corresponding option is grayed out. Any idea what I might be doing wrong?