I just played around with the bump-mapping effect a little bit.
From what I can tell, the effect is (understandably) confined to the sprite you are applying it to.
There are 4 parameters Light X, Light Y, Light Z, and Intensity.
Light X and Light Y both start out with values of 50. Now, I think, though I'm not completely certain, that these values correspond to %of distance on each axis.
So Light X of 50 is half-way across the texture or, 50%. And, a value of 100 would place the light source at the far edge of the texture
I might be wrong, but if this is how it actually works, then I don't know how I would make use of this in a game since this basically means that the light source needs to be static. And if it's static, then that reduces the usefulness of the effect greatly, since you can just bake the effect into the texture before-hand.
I'll try playing with this more to see if I can figure out anything more.