Info dump coming
Mac, MacOS or OSX are all OK. MAC is not. Mac is the machine, OSX and MacOS are the OS. MacOS was the name of the old version, and OSX was the new (unix-based) version, but recently Apple rebranded OSX back to MacOS.
Mac apps are actually folders with a certain structure inside:
<app> has some files and directories. The files have data about the characteristics of the app
<app>/MacOS contains the binary that's run when the app is launched
<app>/Frameworks contains libraries
<app>/Resources contains the game data
<app>/Resources is the only thing that changes, unless the player version is changed. In the past I've taken the PC version, dropped it into the Visionaire player downloaded from the web, and had a fully running Mac version.
Macs can run shell scripts by double clicking, if the script has the file extension ".command".
I had to use brew to install lz4 and xdelta3 to get the script to unpack. lz4 might be ok to include, since it doesn't have any non-system library dependencies, but xdelta3 depends on a library from the xz package, so would probably need to be installed. Or include that as well, and unpack in a location that xdelta3 can find.
MacOS doesn't have shaxxxsum, instead it has 1 binary, shasum. It takes the same arguments as shaxxxsum, and can read the shasums file.