Simplified Mexican Train Dominoes Rules

Equipment

Placement: Match the number of dots when placing a domino.
Doubles: Place perpendicularly, forming a 'T'. A played double must be fulfilled by attaching a matching domino; A player who is unable to fulfill a double must draw from the boneyard. If the drawn tile still cannot fulfill the double, the player must open their own train.
Trains: There are Personal Trains (private sequence) and Mexican Trains (communal sequence). There can be at most 1 communal mexican train.
Train status: Trains can be open (available for others) or closed (available to play for the owner only). Personal trains are closed by default. If a player is unable to play a tile on any turn (to fulfill a double or otherwise) then they must draw a tile from the boneyard, and if they are still unable to play then their personal train is opened if they have one. The player may close their personal train when they successfully play a domino on their own train (so long as that tile isn't an unfulfilled double).

Begins clockwise from the player with the central double.
Play any number of matching dominoes for your train, including 0, so long as they represent a valid sequence. If the player plays 0 tiles by choice or because they do not have any valid moves available, then they must draw a tile from the boneyard.
First turn cannot end on a double.

Play one domino on any available train. If that one tile is a double, then the player is required to play a second tile to fulfill the double immediately if possible
If the player is unable to play a tile, or if they play a double they cannot fulfill, then they must draw from the boneyard. If their drawn tile can be played they must play it. Otherwise they must open their train.

Next player must fulfill a played double. If unable, they draw and open their train. Continues until the double is fulfilled.

First to play all their dominoes wins.
Scoring: Winner scores zero; others score the total dots on remaining dominoes.
Series of games: Sum scores by player across all games. The lowest total score wins the match.

No Initial Double: Draw from the boneyard until a double is found.
8 Players: Start the Mexican Train separately from the hub.
Unable to Start a Train: Place a marker and wait for a playable domino.
Boneyard Empty: Pass and open your train.
First Turn Dominoes Played: Others complete their first turn before ending the game.
No Ending on Double: Must play another tile if possible.
No Unfulfilled Doubles: Must fulfill if you have a matching domino.