I liked the idea, it's very cool and the laser is fun to use. However, I think that there's no need for the slider, since what you really want is either 0.5, 1.0 or 2.0 - it's more elegant that way and also it makes so there's less weird cases to account for (which makes for easier and more bulletproof levels). Also, this is probably the most important aspect of the gameplay, so obviously players will want to have that visible (the slider, I mean) all the time and currently it just takes too much space on the screen in my opinion.
The levels were fun and creative, the learning curve was very good and I really liked that you added rotated robot when on the edge of a platform or a block, really nice touch :)