Two note tremolo how? manual doesn't say

[pianoleo]

Input two dotted quarters/crotchets. You’ll need Force Duration for the second one. Steps:

1. Invoke caret at the start of the bar (select rest and type Shift-N)

2. Type 6. E

3. Type O G

4. Hit Escape to get out of note input mode, then left arrow key to get back to the E.

5. Shift-R ///2 Enter

6. Go to Library > Engraving Options (or type Cmd/Ctrl-Shift-E), search for Tremolos, then set this option:
   

   

7. Apply and close.

End result should look like this: