Good morning, and sorry for my english, I'm Italian.
I am a software developer for audio, and I met a few days vMix.
I usually for video, using Sony Broadcast equipment.
I downloaded the demo version, and I immediately noticed that although being flexible, the shortcuts (including MIDI), NOT have a return, so it is very difficult to use/create an control surface software or hardware.
An example: I possess numerous hardware switches Sony (example Sony bkds 2010).
For me is not a problem to realize a software that allows to control vMix from this surface, but without a return from vMix, it is almost impossible.
Another example: in a couple of hours I realized a software for Windows that allow you, to remotely control via wifi, but same problem.
I "borrowed" from another software the graphics, just to try it, and it works perfectly, but no return... it is useless!
I am attaching the photo, now work Program, Preview, Key 1,2,3,4, Cut, Auto (fade), transition rate.
If anyone is interested I can continue development, for now it is only 10 channels but I can also do 24-32 or more... but without a return (response) by vMix, I think it's just a waste of time.
It works with MIDI (using rtpMIDI) or Web, and works on any Windows OS (XP, Vista, 7, 8, 10), 32 or 64 bits.