That's incorrect. It is only about the slide note. And assigning takes two seconds. Click on Learn. PVST will work for 99% of all other Buzz gens and effects out there. You picked a machine was designed specifically for tracker usage and nothing else, there are very few of these. It is irresponible of you to take 1 exception and then claim the whole thing doesn't work.This is not only only about this slide note - because different machines have their own features which won't be reflected by standard polac vsti pattern which always look the same - no matter, what machine do you use. Many of old buzz machines are good damn ones and I don't want to resign from them and theirs goodies.
MIDI Edit, from within the PXP Pattern editor, works on any machine. Except special tracker only ones that have an extra slide note column. Only the real note column will recieve a note.
As far as assigning things in PVST, you seem intimidated. It's way easy. Just click on Auto Learn and move a couple sliders. Don't bother with F4.