The concept is cool and the game is quite challenging ! The idea to be able to change gravity is a good one ! It allows some really neat level design, and some awesome strategies =) ! The general "hell" design is also pretty cool, this kind of design ir pretty rare.
The only drawback is... I don't really see the relationship with the theme ^^'. You said "Join yourself with the lock to proceed further", but it's like any screen-based platformer... I don't feel like the theme had an impact on the gameplay, or maybe I'm missing something ?
Nonetheless, it's a good game, and I enjoyed playing it !