Thank you all! Glad to get some feedback.
We just added free camera mode. Press 'Q' to toggle between free camera and magnet camera. While in free mode, use WASD or arrows to move.
We're working on allowing players to move objects. This may cause some trouble with the physics and the way blocks stick to each other, so it's not a trivial feature, but we're doing our best to implement this as quikly as possible.
Thanks again, and keep it coming!