Nice work. I agree with Meshon, if the sand is at the same level as the tile floor some would have spilled out. If the sand is contained down in a shallow pit, then you could use an inner shadow to show the depth.

I hope when you are done that you post the whole map at a much higher resolution and size. Even the close-up of the fireplace is still to small for those of us who print battlemaps.
100 dpi = 1 inch = 5 ft works well.