Notation Composer - Lead Sheet from Midi with 2 Melody Tracks (Duet)??

[Scooter]

Hey there!

Im trying to make a Lead Sheet from a midi where the melody (voice) track is not one track, but
on two tracks (staves, I think you call them). I suppose this is common for "duet" songs, such as
ones sung by McCartney & Jackson, Cocker & Warnes, Mathis & Williams - and so on.

I don't seem to ba able to find any information as to how to include BOTH tracks into the lead
sheet. At the moment I can produce a lead sheet with either voices - and blank bars when the other
track is playing - but not with both voices in the one lead sheet.

I wonder how people manage if there's a "Boyband" with many voices involved...?

Thanks for any help

Cheers

Scooter