[GLSL] using a LightSource as Timer for Shader Animation

We had a strange Idea in our Forum. We want to use the Position of a LightSource as Timer for Shader Animations. We think this have some Advantage.

Special that LightSources (Lamps) can run a Shader without to restart the whole Shader-Script. Now, its not possible to save Values to the next Shader Cycle. We think, that way it is. There will be more komplex Animations possible without any Python Stuff. All works inside the Shader. Only 1 Lamp as Global Timer for all Shaders.

It works theoretical, but here are some Problems. Maybe someone can help us out.
Here is a little Demo File with a small linear Textur Animation. File here

The Camera is rotating around the Plane. And The Texture seems to move in Relationship to the Camera, in Speed and Direction. But thats wrong.

If the Lamp moves 1 Unit, the Texture should also move 1 Pixel, independent to the Camera. I don’t know how to solve this.

Can anybody help?
Thank You.