Light Layers have importance weighting that is linked to the total Flux amount of the light layer!
if in a scene with 2 light layers the first layer has 100 times higher flux then the second one, the first layer get also 100 times more of the processing power assigned by indigo!
small light sources often have this problems, their layers evolve very slowly.
raise the flux power of your light layer to work around this issue, and reduce Light Layer intensity in the Indigo GUI if it gets to bright...
I hope this helps
