I just looked it up, and the Engraver fonts don't come with Allegro. But, you can change fonts mid-way. For Example: select Maestro font, input the note you want, go back to font menu, pick a different font eg Times New Roman, and continue typing as normal. Changing font only changes the writing to the right of the cursor, it doesn't change everything if that makes sense.
Oh crap, you just wrote what I just typed up
Perhaps you could include this in the guide?
Yeah, EngraverText has notes in it. I just checked. w=whole, h=half, q=quarter, e=eighth, x=sixteenth
Edit: woops, make that e=eighth