Thank you for your feedback. We realize that the game is difficult and that some puzzles are hard for you to solve. We've read all your feedback and we would like to assure you that all the 128 levels have their solutions. There are no errors or bugs. From now it will not be a problem - we have prepared a hint mode to facilitate. Now, you can buy keys with a hint, and then use them, but it's not necessary to solve the puzzles. You can use them or not. The choice is yours. It’s time to update!