Grishka's suggestions are all good.

Do you read music, Morwen? Have you seen the music for 'Twilight in Barakeesh' as well as heard it? Because I have encouraging news for you - that MIDI that you linked is way too high. A gifted coloratura might be able to hit those high notes, but they are not doable by ordinary mortals.

The highest note is a G# above the staff. In my church hymnals, the highest note ever asked for is the Eb below that.

I think what you have there is music written for an orchestra. Instruments have bigger ranges than people. Yes, somebody may have set words to it and given it to a trained singer, but it's still not really a vocal piece by nature. So don't be discouraged that it's hard.

I have MIDI software would you like me to change that MIDI so it's lower? I can make it play within the normal range for a soprano. And if it doesn't work, we can do it again. But you have to let me know, so I can send it to Joe for posting.

Another thing about the song - was it a duet? Maybe one person took the low lines and another took the high lines. That would make it quite hard for a single person to sing.

By the way, the song is a riot. I love it! Thanks for finding it and posting the link.