SO far, the GOG.com version of Fallout: New Vegas has been smooth and no crashes. here were the settings from the game launcher.
In Graphics Adapter and Resolution, I entered the following:
Graphics Card: Intel HD 4000, Aspect Ratio: Standard, Resolution: 1024x768, Antialiasing: 4 samples, Anthroscopic filtering: 8 samples.
For mode, check vertical sync, for screen effects, check only HDR, and check the box marked: show all resolutions.
Windowed mode and other specifications entered in options for me with Crossover have resulted in a bug where the mouse cursor leaves the screen, and the game is not genuinely fullscreen either.
If people on computers with other specs find ways to run the GOG.com version smoothly, feel free to let us know your specs and how to do so. This is just for a 2013 MacBook Pro with Intel HD 4000 card.