Re smoke, its a mixture of steel wool (used for delicate sanding of wood and the like) and cotton wool, with a smattering of black poster paint over both. They were orginally part of shellbursts that V.I.Blackwood constructed for an early game (with wire and plaster bits in them), but as they fell apart through age and use, the resultant detrious looked spot on. I would therefore experiment with steel wool, cotton wool and paint. Hope that helps