On the Support & Technical Forum which doesn't have much traffic anymore, new Forum member Fred Goldrich posted that he doesn't have volume control over 16 Garritan instruments. They're all part of the Finale Default Bank, and are originally from GPO and World. Here's his thread:
Lack of volume control in Finale Default Bank
MakeMusic Support has now told him that he's uncovered a bug which they hope to resolve in a future release.
As I told Fred on his thread, I wasn't aware of a volume problem, because all the instruments in his list work normally when I test them in ARIA Standalone, and they also work when I open ARIA in Sonar. So it looks like things are working fine in DAW software, but not in Finale. I suspect that things work correctly in Finale when the full versions of Garritan are used, and that it's programming in this Finale Default Bank which got broken.
It would be helpful if you Finale users could double check this. If you don't have the same problem with these instruments, it would be helpful for MM to know that.