Tom and Gary,
I've been looking at JABB the last couple of days in light of using this with Sibelius. It occurs to me that it could be useful if the brush snares were modwheel controlled rather than velocity controlled. This is a continuous sound after all rather than a percussive sound. And with modwheel support we could add hairpins to effect the brush direction rather than aftertouch and this would fit nicely and be a bit more intuitive with notation programs.
I've got a Sibelius Soundset for JABB pretty much completed. I'll post a copy in the few days. Just a few odds and ends to clean up. It uses an undocumented feature I discovered to enable the Sibelius midi controls to external sampler players like Kontakt or Garritan Jazz. So it works much like GPO Sibelius edition but without the need for a JABB Sibelius edition.