This game is a diamond in the rough. The closest game I can compare this too is Lines of Action, mainly due to the connection goal, although the similarity ends there. I consider Cluster to be the superior game mainly for its clarity and depth. The combination of connection goal, variable height pieces, and the ability to jump over a file, add to the strategic potential of play in a balanced way without adding excessive complexity to the game. There are many positional elements that arise during game play such as forks, pins, managing degrees of freedom, and timing. In a manner similiar to Chinese Checkers, both friend and enemy pieces can be used to ones advantage. Draws due to repetition are possible, but occur infrequently.
This game played a big part in developing my interest in abstract strategy games. It is also one of the few games that my wife and kid will play. Don't let that fool you though as there is much more to this game than first meets the eye and therefore it should only be judged after several plays. The interlocking pieces offer a novel game mechanic that's largely responsible for the substantial depth and strategic complexity of the game. The 7x7 board seems to be well balanced size for this game.
I have some questions about the "close off" moves. The rules only show examples of placing a tile which closes off paths leading from that tile. What happens if placing the tile closes off paths on other, adjacent tiles? Are those considered "close offs" too? If so, does the scoring follow the color of the tile placed or the color of the path (on the other tile) that was closed off?