Far to many problems with the game for more then 3 stars.
The grid is far to small to make meaningful combo's and you can get grids with no combo at all meaning you can't break even a single shield. This is just fairly boring.
The skills might as well not exist except the basic one. Most games are finished before you get enough points to use them, or at least the gold medal is gone anyway.
The tech counter at the top, which I think is suppose to grow in size as it goes up, doesn't shrink again so it was taking up over half of the play area.
The story was nice, but the game play just wasn't good enough to match it.