I think I understand what you are asking. You've applied the lighting effect to the layer with the content itself, whereas what you want to do is create a new solid layer and apply the lighting effect to that. Does this solve your problem?
Switch the Transfer Mode within the CC Light Rays plugin to "None". This will switch off the source layer content and only display the Light Rays themselves.
Applying CC Light Rays to a solid won't work, as it will not have any connection with the source layer.
Andrew is right, but if I'm understanding this correctly, color from source is checked by default.
This needs to be turned off as well for the light effect to appear with your footage.
You proabably also want to duplicate the source layer and place it underneath the layer with the new CC Light Rays Transfer Mode settings...
Actually, to see it initially it either needs to be off, or you'll need to move the light around pick up the color from the underlying source.,