Hi Stog. Yes, as indicated in my initial post, I am aware that GNUBG ad GBBLITZ both work well with macOS X; and both are getting excellent reviews.
However, neither one of them is on the App Store. Do you know why? One would think that with apps that strong and with such good reputation, the developer would want to make their software available on the App Store, thus giving prospective buyers a peace of mind, knowing that the app has been vetted by Apple/Microsoft (as the case may be.)
True Backgammon HD is on the App Store, and it uses the BGBLITZ engine; and while the reviews for iOS are pretty good, they're awful for macOS. Is anyone here using True Backgammon HD on a Mac? Thanks again Stog for your quick response - appreciated!