Exactly. I seem to be using the wrong terminology here but in effect I am trying to say what you are.
I understand and that is why I gave up on the color ripple texture mapped to the flat plane I was originally shining light through. That is why I decided to use a high contrast black and white texture map on a flat plane, either positive or negative add transparency added so the shadows would be created by the lights filtering through the transmapped plane. What I understand is that the transmapped flat plane will work as a mask...sort of like pointing a light at your hand..it is opaque so it casts a shadow on the wall.

Are we on the same page now!?  :)