Derived with help from John: johnno1962/InjectionIII#487
This is for the GitHub version of InjectionIII. I can't get the app store version to work. You have to run the app and choose "Open Project". Don't choose "Prepare Project"
I can't get it to run in standalone mode (maybe the trick is to reset or remove com.apple.security.app-sandbox in MacOSWithInjectionIII.entitlements).
The rest are in the commits in the repo.
Unlike most repos, I intend to force-push to this repo instead of adding commits because it's meant to show specific steps to set up a new project.