Allow [Shift] + MIDI Note Input to add note to ChordRest of current selection
2.0.3 / Win 7
1. Using a MIDI keyboard, enter 4 quarter-note closed hihats on a percussion staff.
2. Go back to the first hihat and, using the MIDI keyboard, try to add a sidestick, say, in the same voice. AFAIK, it's not possible.
There is no procedure to allow you to "subsequently" add notes like this from a MIDI keyboard. In this case, you have to start again by entering the hihat, keeping the F#1 pressed down, then entering the sidestick by pressing the C#1.
Suggestion: Allow the Shift key to be used with a MIDI keyboard, as it is with the (2.1) virtual piano keyboard, to add notes to an existing note.