Thank you very much for your generosity in devising and sharing this. It does make one wonder why Sony hasn’t provided it.
can anyone tell an average person how to get this installed on a Mac and use it and how to use it?
Terry you need to use the Mac version rather than the PC version. It's on GitHub but if you don't want to pull the source and everything down you can get just the application from my
DropBox
Once you have the app you can drag it into your applications folder or just run it from wherever you like. When you run it you have very few options. Select the number of frames to capture, Select the Shutter delay between frames and select the time to wait for the focus to move. The defaults are probably fine I tested them with my A7Riii with a Batis 25 attached. The delay between shutter actuations is to give the Remote app time to do it's stuff with downloading the captured preview etc. If you can find a way to configure remote to not download the previews then you can set the delay much shorter. Conversely if your Mac is slow you might need to increase the Shutter delay
There is a check box marked Home which if selected makes the focus move to the minimum focus before starting. If you want to focus somewhere else and step from there uncheck the box.
The radio buttons let you select the granularity of the steps. Fine takes about 300 images from closest to infinity on my Basis 25. Medium takes about 80 and coarse about 20. These were just random choices. Please let me know you thoughts on granularity. Its not possible to do it by distance but it can easily be changed to let you put in a number rather than the radio buttons.
Once your set just press Go and if Remote isn't running it will launch and then it will start taking images moving the focus point between each one.