I ended up dropping the game after one "brain weight" test. Simply put: The game itself is fine, but the unpolished presentation and lack of scaling for HiDPI monitors makes it simply *feel* bad to play, especially in relativity to playing Brain Age on MelonDS. If you want a charming game that'll help you train and test your mental acuity, go (legally) obtain a ROM of Brain Age for the DS and play that instead. Roughly the same size, far superior game.
I have most of the games open, and they are great for building and maintaning mental agility. One game (bomb hunt) gives a failing score for solving the puzzle, and the symbolic logic game does not seem to make nuch sense either, but most of the games are highly entertaining and challenging. Even with a few rough edges I recommend it very highly.