Saving area lights as presets

I am having a problem. If I save a preset with an area light plane, the headlamp blocker and 2 distance lights, when I load it back in the area light plane is gone. Is there something I need to be doing to save my light setup? Any ideas would be appreciated.
Comments
An object with an emissive shader is not seen as a light, you need to save as a scene subset.
OK, makes sense. Thanks!