MacReady's chess machine
Does anyone know what program/machine he was using during the film? I think it might be "Computer Genius 1.3" but im not sure.....

The machine he's using is an Apple II computer dressed up to look like a dedicated chess machine. I'm about 95% sure that the software running on the Apple is "Sargon II," a very popular chess program from the 80's.

Mac's chess machine
Has anybody worked out the position on the screen and is it from a real chess game?

There are two constellations that have nothing to do with one another or even with the moves that are called out. Could be laziness, but maybe Carpenter wanted to make absolutely sure that no one looks at the game as a carrier of meaning but only at Mac pouring his drink into the computer when he loses.

I like that game :P How boring it is when you have to chess all day to ammuse yourself.