Here is an almost-working patch for a device handler which enables the first six buttons in the new app:
Note that this has “pushed”, “held”, “double” and “down_hold” actions, so there’s no need for virtual buttons 9-16; we would just need a vid which supports configuring 8 buttons in the app.
The above code, if you change it to 8 buttons in getProdNumberOfButtons, should work well for the classic app.
Unfortunately, even with 6 buttons, which display well in the new app, attempts to set actions for the buttons fail with a generic “server/network” error (for me, at least).