Sphere Reflection Capture only way to get blue color baked onto black object??

In my scene there is a long row of curtains, and just above them, large projector screens. In between the screen and the curtains I have quite a few blue lights pointing down toward the floor. Strangely, when I move the lights, the blue is easily casted onto the ground and looks great; however, after I build the lighting it just goes away. Why is it that after the build it stays nicely on the curtains but not on the floor?

There is nothing fancy being done in the curtain or floor materials (spec isn’t turned down to 0 or anything). All the objects and lights are static. I understand lightmaps fairly well, and as far as I can tell this has nothing to do with UVs or resolution, etc.

Now one thing I noticed is that if I place a bunch of very small-radius sphere reflection captures where the blue light should be it shows up. One problem with this is that it’s view dependent and looks quite strange (blotchy, and there’s a black space between the curtains and floor). I wouldn’t expect a blue light to only show up in the presence of a sphere reflection capture…

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Finally, as I change the color away from black and towards grey, the blue will progressively come back in and look great. However, I don’t want blue lights on a grey floor; I want blue lights on a black floor.

Any ideas? Thanks in advance.

The sphere reflection capture is not enabling your light, it is capturing it from the blue light on the curtains and reflecting it on the floor.
As for the light not casting on the floor; is it giving any error messages after you bake in the message window?

Nope, no error messages whatsoever. As I mentioned, it is directly tied to the fact that the color of the floor is black (or very close to it). As I drag the color slider away from black and towards grey the baked blue light on the lightmap comes back proportionately. Is it just that blue lightmaps can’t be rendered on black materials in the engine?