What does this do?? I get an error: internal error when I put in a Game # that I noticed at the top right of the game I was playing with a friend, hoping we could finish the game we started a previous day. How does it work? How do I use it? I chose Load Old Game and put in the Game #. I guessed that's what is meant by "Game Id." But, it didn't work. It just said "Internal error."
It works exactly as you think it would, with the twist that sometimes, for reasons unknown, the game cannot be loaded and it gives the ominous "internal error". If you increase the number by 1 or 2, it likely will load that game (but not help you with continuing that original game).
It's used for example to look later at a game you played to see what you could have done better, or what your opponent had in hand in a critical situation.
I use it to check bug reports. Often there are circumstances that the player forgot that explain something that at first sounds like a bug.