Lighting effect does not render

I opened a new Rhino file then set up a simple surface.
Above this surface I set up a working Spotlight then rendered the effect, it,worked.
I imported the model which fails to render its lighting effect.
Once imported I deleted the original lighting effect which was imported with model
I then copied the new models light source (which was above the simple surface) into the imported scene.
The light source inserted into,the scene is now rendering.

Hi,
Basic lighting application, I mean Create Spotlight, Enabled.

  1.  I checked the box: V-ray Option Editor>Global systems>Hidden Lights. (Is this the Render Hidden Lights switch?) The lighting effect did not render.
    
  2.  I opened a previous model in which the Create spotlight effect renders successfully. Then unchecked the box Global systems>Light then rendered the scene, as expected the lighting effect was turned off /  did not render.  This is the effect I appear to experiencing in my model which fails to render the lights.
    
  3.  I can produce three models in each the lights work. In the next new model, the lights do not render. The next new render the lights will render.
    
  4.  In summary, I have one model where the lights render. The next model, the lights fail to render.
    

Peter