Hi Tim,
Thanks for your comments.
In regard to Sharesong, I haven't actually seen any details on their criteria for song inclusion, but I would think they are probably into the more popular 'Praise & Worship' style of music. I know that these days both Protestant and Catholics sing a lot of the same songs.
I would doubt very much if Sharesong would be into anthing like Mass settings, but then I don't really know.

In regard to the vocals. The computerised vocals are done by some French software called 'Virtual singer' from www.myriad-online.com. Its costs about $20US for the Melody Assistant program and you get Virtual singer with that. You supply a midi file with lyrics into virtual singer (eg a midi file from Composer works fine) and the thing sings(?) the words. It sings much better than I do. You can do lots of adjusting to it change the sound, and pronunciation.

BIAB is as the name suggests a Band of 5 instruments. It takes a melody and chords and will play it in the style of virtually any sort of band - mainly jazz, swing, rock, pop styles. It is supplied by www.pgmusic.com.

BIAB also has a music creation process as well, where starting from scratch it will generate a melody and chords. This is a facility I use all the time, as I'm not an original composer of music. The BIAB features allow me to change and redo bits of the generate music until I'm happy with it.

BIAB does have a scoring facility as well, but it pales into insignificance compared to Composer.

Hope that helps. Incidentally, I notice you are from Adelaide in Australia. I'm just along the road from you - used to live in Melbourne, but now gone west to Perth.

Cheers ... Clyde