1. Write your music in Sibelius using the VDL2 Template. Don't use Finale because it's ugly, cumbersome and bloated :)
2. Export a MIDI file
3. Drag-n-drop the MIDI file into Garage Band
4. Double-click each layer to assign VDL2 sounds to each track:
a. Expand ";details"; b. Under ";Generator"; select Virtual Drumline 2 c. Click the edit button (looks like a little pen) and it opens the VDL2 Player Interface d. Pick the instrument you want for this track only. Do not load multiple instruments into the VDL2 player. e. Save this instrument and pick a name for it and you can use it again later!
5. Open the Track Editor (the scissors looking icon) and fine-tune your MIDI data. Adjust velocities to improve your dynamics. It's a fairly simple interface and easier to understand than most other audio software. Tweaking the velocities is a tedious process but necessary for a realistic recording.
6. When you are done, choose File > Export to iTunes. Garage Band will then create a mixdown audio file and open it in iTunes under a new playlist. You can find the file by right clicking it and selecting ";show audio file"; and it should end up in your iTunes music library in a folder called ";import.";
The only drawback to this method is you need a separate VDL2 player for each instrument track. The bonus is you can save the instrument settings for use in other projects. Garage Band is also a little more sluggish than other programs and you may experience more drop-outs on a slower computer. On my Mac mini I had to export the pit and battery separately and mix them back together again. The best part is Garage Band is FREE with OS X and your final project will sound A LOT better than recording straight from your notation software.