These BIAB crashing issues were driving me absolutely nuts.
I think I fixed it. So far no crashes when using H.S. channel volumes or other VST settings.
What I did:
1) Uninstalled H.S. (I reinstalled it before, did not help)
2)Uninstalled BIAB
3)Clean install Halion Sonic version 3.2.10.94 (64 bit) Oct 12/2018 (latest)
4)Installed BIAB w latest 612 build.
I hope this helps to somebody in same situation.
Misha.