This versions of GiD works on macOS 10.9 Mavericks or newer.
Note for macOS 10.15 Catalina: The first time you open GiD, macOS will display a message about opening an application from an unidentified developer. Just dismiss this window and Control+Click the application and select open. Now the window will show an ‘Open’ button to launch GiD.
Official versions of GiD are stable versions of the program. They don’t include the newest capabilities but they have passed all the validation tests.