Hi Wendy

Well as you say a sgu file I assume the melody and soloist track are free. So you can put midi notes on those.
Just insert a midi instrument on the track. This will need to be a continuous voice not one with a natural decay like piano , say a flute or pad as you say.
Then insert a single note in the first bar it is to sound in notation view and stretch the note length for the number of bars you need in piano roll, or editable staff mode notation mode and stretch the horizontal red line
Hope this is what you need
Mike

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