Here’s an overview of how I’ve set up Companion to make switching easier on the ATEM Mini Pro ISO - Program/Preview cut bus, keying, macros, and VLC playback.
You can download a copy of this Companion profile on my blog - DavidJoshuaFord .com/production/companion
Thank you for sharing your companion files! I was impressed after seeing the demo of this and the VLC one on your youtube channel and immediately wondered if you could share the hard work you put into it. Thanks again and keep up the good work.
Thank you so much!
Finally I can learn how this works by tinkering with settings, with your example. 
FYI, this layout has had a whole new update as of February 2021. Get the details at https://davidjoshuaford.com/production/companion.