The in-game achievements are so buggy. Gah - can't get lower level achievements if rank increases twice. If the rank achievement is not given yet and rank >= rank needed it should give achievement.
Hmm there are some bugs.
I can get one line to be marked as solved with a different number of blocks marked in black. On a grand master puzzle one line is 1 2 2 4 1 1 and if I remove the second last one then replace it with an X it greys out as though the line is solved.
I dont know why people are complaining about the AI, it seems to be exactly the same AI as the arcade version, and champion was not really a very hard version. However, the arcade version had random character order and a base difficulty stetting in the machine. It would be nice to have these features here.
Should allow continue from any level, and perhaps instead of straight guess include a clue button or at least some cryptic clue.
To make this into a better game you could make a bunch of levels that are rated by difficulty (obscureness of the number) and randomly select each level. Each level would have some cryptic clues at the start and the player can spend some clue points to get further clues. You could also include 'lives' letting people fail a few times along the way, maybe when a life is lost a clue is also give, so one must balance clues and lives and guessing to succeed. Anyway just some ideas.