The Xbox Live game mode is a bit broken, saying "You need to be signed in and connected to Xbox Live to access the functionality.".
In order to bypass the problem, you need to sign out of your profile and sign back in on the game's menu.
Get yourself a boosting buddy as this game is dead online. Both of you search for a ranked match (this can take a very long time... 5 minutes at most). Once you two are put together you will both be randomly chosen as the black/white stones holder.
If white wants to win, have both players pass without placing any stones. White is always handicapped a few points at the start.
If black wants the win, get black to place several stones down and white to keep passing. Both then pass until it concludes black will win. If it's not enough, you can continue until you get it.