Wiki page: http://www.wargear.net/wiki/doku.php?id=boards:go-geared:go-geared
Playing and Moving Stones
All attack and defence dice on the board and from the bowl are "8-sided." This gives defender a slight advantage. Attacker loses approximately 57% of the time. Surprisingly, there are times and positions where it appears to be correct strategy to attack, but you can make this determination yourself.
Abandon is ON, but when you move a stone you leave a funtional "blank" in its place. Blanks count towards both capturing territory and meeting the victory condition.
You get two moves per turn. Generally, you want to play one stone from your bowl to the board and move 1 stone on the board, though technically you could move two stones on the board and elect not to play from your bowl. Use it or lose it.
Capturing Territory and "Turning" Opponent's Stones
Capture territory by surrounding it on three sides (borders). (The four corners can be captured by surrounding them with just 2 stones). If that territory happens to belong you your opponent, it becomes your territory. Captured territories receive stones with a singe unit.
You must have the territory surrounded at the beginning of your turn before it becomes captured.
Winning the Game
Fill more than 1/2 the board to win. This is a two-player game. Like the games Chess and Go it is appropriate to resign (surrender) when you are sure to lose. There's no need for self-flagilation, and besides, be considerate of your opponent's time.
When you have won, the player will give you a bonus unit at the beginning of your turn. Place that unit on your color in the Yin-Yan symbol and attack from there to your opponent's bowl.
Minutia (ignore unless something about game-play seems wrong):
The victory bonus requirement appears 2 units higher than expected, but is necessary to account for the impact of the bowl and the yin-yan territories on the territory count.
Occasionally a stone or territory will not "turn" even though it is surrounded at the beginning of your turn. This is likely because one of the capturing stones was just turned itself. This stone will be captured on the next turn if the capture conditions still exist.
Thanks to Alpha and Hugh for early Dev work.