Pretty cool game.
Although like you say in the description, it is a bit small, so that's kind of a draw back, but at least you knew this before being told.
I think I found a bug, it's possible to get literally stuck or cut off from the stairs, this happened to me at level four. I got boxed in and wasn't able to get to the steps.
One more thing, it's not so much of a bug but, if you turn on the "hold to move" option and walk into a wall, the stepping sound keeps playing in accordance with how long the button was pressed instead of, if it is currently being pressed. not bad just a little counter-intuitive.
Also, sorry one last thing, a "game exit" or "return to menu" option might be nice.
Anyway, Cool Game!