just a suggestion...perhaps another way the devs could handle this situation is to instead of actually attempting to "scale" anything. Just detect when venues are switched and any of the instruments have moved out of hot spots..then nudge them to the closest location that is inside a hot spot. Keep track of the last known position of each venue, so that if you switch back to the previous Venus, it will pop back to the location where you had it. Actually if you think about it, you could end up having each venue remember the x,y,z offset of every instrument on its stage..so that if you switch venues, it would use the last known position when you edited it on that venue maybe..something like that...
Or if nothing else, flag the ones with bright red that have been unwittingly moved out of the hotspot by changing venues....
or another idea would be instead of scaling down the arrangement of players on the stage, instead just scale up the size of the venue so that everything fits. or something along those lines. it doesn't have to be that complicated...just a way to avoid instruments dropping out from audio when trying different venues.
Or perhaps a third option would be to have an option where if an instrument is not inside the hotspot area...you can tell MirPro to always use the closest position that is still within the hotspot for those instruments that are off in the dark. That way they don't just disappear completely from the sound. Flag them bright red or something so that we know we need to position them where we actually want them. In that way, nothing has to actually be scaled...you only need them to keep making sound when you switch venues so you can quickly hear what each venue will sound like more or less. If some of them are slightly off the hotspot area...fine...keep making sound using the closest point in the hot spot...with indications that we should think about moving it into the hotspot.