The name "Gravity" as well as the genre "Puzzle" were derived from the original idea (meanwhile I have changed the genre to "Other" and added "flashing lights" to the sensory info).
That the description gives a wrong impression is probably due to the fact that I described my original idea there, which unfortunately was no longer applicable to this game.
I can understand that the levels were not well-balanced and not really predictable and therefore unfair.
I'll probably do that better in my next game.
Thank you for your detailed feedback.