Complexity in Help Screens

I'm wrapping up a Mancala-style game and the rules are fairly simple: the board contains twelve pits with four seeds each to start, players alternate sowing seeds from a pit into subsequent pits, if the player drops a seed into a pit already containing one seed they are taken out of play for two points, and, the winner has the most seeds at the end.

Some of the finer points are handled by the game such as which pits belong to which player (colour coded) and cases where a pit has so many seeds it goes around the whole board past where the player started.

Because the engine handles certain rules, I'm debating how to explain them to the player. I have four help screens with a small label to write instructions because I have to leave enough room for an interactive board that helps explain some of the instructions. I have a couple of ideas:

1) A 'more' or 'detail' or '+' button in the corner of the label that expands over the board and gives the same instructions as before but with more detail for players that want more explanation.
2) A help screen at the end with the heading 'advanced topics' that is a solid page of text with some of the more esoteric rules which the player doesn't have to manage or may only rarely encounter.
3) More help screens in general.
4) A comprehensive description of the game and rules as an external PDF or web page.

I'm leaning towards (1) but any feedback or alternative ideas would be appreciated.