I love M.C. Escher. Since I was a little boy I wanted to walk into his labyrinths. And there come the first level ; Wow. The dream come true. I was amazed.
But after 30 minutes on the game, I had a few things to reproach. I was not surrounded my the Escher Magic anymore.
The unique gameplay is only shown on Escher's level
Indeed after the first level the player face puzzles that are almost exactly the same as Portal ones, but with the non-euclidian gameplay. A cube, a button that open a door, doors that can "warp" you to an other side. A player that has played Portal already knows all the patterns about the great majority of the puzzles.
I think you should have drown your levels as simple drawings first, just trying to take up Escher's style, and not working on level design first.
The second thing that bothered me is a problem about level design. This game deals with labyrinths, and usually the direction the player must take is very unclear. Thus he attempts a way, but finish blocked and must restart the level from the beginning. This is not a cool game design, a player shall not be blamed for his curiosity and exploration.
Let's take the example of Portal, because it's the closest game. The levels are build so that you never have to restart a level, you can always "restart by yourself", going back to a point of the puzzle and re-create a cube if you have lost yours.
A last little thing, the font is not going very well with the voice. When I read it I feel the unfinished game. Maybe a font more holy, massive would be more appropriate.
Finally other than those things, great job. It will probably be one of my favourite games when all those troubles will be set.