Not sure that I understand - you can control BVars right now, it is just a little more involved technologically for the app that is doing it.
In case of your unmoving switches, that is probably the usual split logic. One part of the behavior code is actuating the aircraft system, the other handles the animation of the 3D switch. You just have to find out how the animation is handled (often by an LVar or A:Var or combination thereof) and replicate that in your app (I’m sorry, but I know nothing about how SPAD works). With BVars and IEs that becomes a lot easier - IF the aircraft developer can be bothered to use them and implement them correctly. A small part of detective work will always remain.