the WorldPosition(v3) takes in the world position of each pixel so that the function can turn that in to a world-aligned texture.
I’ll explain why what you’ve tried isnt working:
-plugging in a static number to that input would break it, as you’re telling the function that each pixel on the screen is exactly the same.
-plugging in the AbsoluteWorldPosition would do nothing, as that’s what the input already takes as default, so you’re overriding it with the same thing.
You’re half-way there though!
All you need to do is get that AbsoluteWorldPosition node and *add or subtract to it the amount you want to shift the texture.
in your case, if you want to shift your texture down in the z-axis, Because the coordinates are stored as X,Y,Z, you need to subtract '0,0,’ from AbsoluteWorldPosition. In this image, I’m shifting the texture down by 1 meter:
Hope that helps 