Thanks All,
Dune, every time I restart TG and run Danii's classic erosion I get a slightly different result and some times the stream beds are slightly tilted and as they drive the water surface masks, they some times tilt. I have been able to compensate a little by adding some positive displacement. In this case though the water is flat and it's the angle of the foam that creates the illusion(I think). Another issue is that masks from the erosion filter cannot be adjusted for width very much, exported maps would be handy. The cloud is a matter of taste, in my years photographing the dawn I saw many strange clouds! and I like the sense of darkness receding from the light the dark cloud gives. Stream water is usually this transparent only becoming murky further down river unless it's glacier water which green and milky.
Another annoying issue is every time I restart the the program I get different fake stones!