I'm having a similiar problem. I have created a rainy area with water splash sprites on the ground and I would like for there to be a thin, transparent sheet of water over my floor. I tried creating this effect with func_walls, func_illusionaries, and slow moving non blocking func_conveyors. I then tried it with func_water. First attempt had the func_waters textured as {blue and then applied water texture only on front face. I followed tutorial directions to create transparency with "texture" effect and "100 or so" on texture amount. This yielded a solid rendered water on the floor, but not transparent. I then applied water texture to all sides of the entities and on the next compile I was drowning.