With regard to the second dream, underground rooms/caves/mines are usually seen as signs of spiritual exploration, I believe. Your desire to see further spiritually is limited by the light you have worked out how to turn on. Having your (unspecific) friend there suggests that you are not alone in this situation. Your noticing the grid of lights there suggests that you know that more light is possible and so to me it suggests that you need to focus your spiritual work less on exploration and more on upping the light.