Thanks all!
Maybe it's that I am running Android 5.0 on a Note 3, but I can't find/see an aquamail shortcut or activity that is 'new message'. I do have Button Mapper 1.51 by Aaron Segaert installed, and also Next Launcher. In Button Mapper for instance, for buttons I have a menu of: actions, applications, shortcuts, system, media, and advanced - but can't find aquamail new message anywhere.