In order to play, you need an oval field. There also need to be three hoops on each side. As you can see from the config, the last value indicates the material the goal area needs to be made of. The default is web, so just fill the inside of the hoop circles with web blocks. Those will be taken out at the beginning of a match and replaced at the end. Make sure all web blocks in each goal are touching each other on a side. If your goal is just a regular circle or something, you won't have to worry about this little detail, as all web blocks touch each other on the top, bottom, left, and right sides.

To start the game, you need to run this command: Qstart 100 50 Gryffindor RED Slytherin GREEN [referee name (optional)]

The referee name is only required if running the command from the console. Usually you would get the referee to run the command. The first value is the north-south width of the oval field. The second value is the east-west width of the oval. The third value is the name of the team on either the North or East side (depending on which way your field is oriented). The next value is the color of that team. The next value is the team name of the one on the South or West side of the field, then their color. If you specify a color that isn't valid, the color will default to white. The colors specified here are used for the color-coded announcement messages.

All of these dimensions of the field are based on where the referee is standing, so make sure they are standing exactly in the middle of the field.

When the command is executed, everyone playing needs to be on the field. Anyone in the field boundary (besides the referee) will be considered a player. All players will be notified of their positions and teams. The positions have to do with your distance away from the referee and which side of the field you are on. The players farthest away from the referee on each side are the keepers, followed by the seeker, then 2 beaters, then 3 chasers. It will stop when it runs out of players, so, for example, if you have 3 players on the field, one is the referee, then if the other two are on different sides of the field they will both be labeled keepers. If each team doesn't have at least 1 player, the quidditch game will automatically quit before it starts, which is why you need at least 3 players to play a test game with only keepers.

Once the command is given, an alert will go out telling the keepers of each side to click on each of their three goals. Each referee then needs to click on a web block in each goal. You can tell if it was successful because the web blocks in the entire goal will disappear when one of them is clicked. Once all six goals have been clicked (3 for each side) the quaffle will be given to the referee, the snitch will be spawned 50 meters above the referee, and the bludgers will be active.

Once the game starts, the quaffle will be given to the referee. To throw the quaffle (only chasers and keeper), catch the quaffle (only chasers and keeper), hit a bludger (only the beaters can do it), and catch the snitch (only seeker), you left click. The referee starts the match by left clicking into the air, throwing the quaffle. The quaffle will fall just like a normal block, but at half the normal speed.

The referee can assign penalties to teams by facing in the team's direction and left clicking (this function is disabled when the referee is holding the quaffle at the beginning of the match). This assigns a 5 point penalty.

Most actions in the game should be narrated by the announcer system. Anyone playing the game and anyone in the oval 50 meters larger than the game oval will be able to hear the announcements. This allows for a spectator area.

Points are scored by throwing the quaffle through the goal area. You cannot fly through the area holding the quaffle, that won't score a point. When a quaffle is scored, the quaffle is then given to the keeper of the opposite team, which then should throw it back into play.

Chasers and keepers can hit the person holding the quaffle to steal the quaffle from them. All three balls are represented by block break effects (like spells are in ollivanders). Which block break effects you see can be configured in the config.

The game is automatically ended with a snitch catch. The referee can end the game early by using the command /Qend. This ends the game and provides a readout of the scores. The permissions Quidditch.QEND and Quidditch.QSTART are required if a player who is not op wants to start a game. The referee of a game can end the game regardless of whether they have the Ollivanders.QEND permission.

Balls will bounce off of blocks and the field boundary. Players in the game cannot leave the field while the game is on. The field only encompasses the horizontal oval specified, and goes up and down infinitely. Make sure you don't mix up your first and second numbers in the Qstart command, as that is really easy to do.

Keepers cannot leave their half of the field. At the start of the game, all players' spawn points will be set to the middle of the field (in case they die) and then reset to their previous locations at the end of the game. Let me know if this feature in particular is giving you bugs, as it has in the past.
A note about bludgers: they zip around and try to hit players. Only beaters can hit them away by left clicking. If it hits you, it doesn't hurt you, but it does cause a velocity change for you (like you have been knocked off course) and a little nausea effect. Bludgers will not chase a player that their brother is chasing, so you can have at most one bludger after you at a time. Bludgers will not go after the last player they have hit. This is the expected behavior with a full team, but as you can imagine with 2 players total, the bludger won't follow these rules exactly because when it hits a player, the other player is being chased by it's brother, so it can't choose a player that hasn't just been hit by itself and that isn't being chased. At that point it will choose a player at random.