WIP2
This is the best I could come up with. It needs minor adjustments, lined up and light color and level tweaks, but I think it looks pretty good.
Halos only, -3 below surface
Holes with the blue plastic.
A wall set at -4 to hide hole sides and bottom (the sub-floor is too bright)
A single decal mapped to the wall below that shows a light off state.
So basically what we were talking about but the halo above the lense though it looks the same as if it were a bit below. No transparency is the reason for that.
If you can improve on the method that would be great, but I have to say I'm happy with this.
The code is the matrix block and the subroutine below it, for all I know that is all of it.