Thanks, Martin. Yes, I decided to keep the snow in fractal form. This'll make it easier all round for people of all skill levels to edit it, if required.
I have other attempts at functional perlin snow, too, but really, my fractal lines issue was the main hurdle I was facing. That is now fixed. The only functional part of the shader set now is the sparkle effect.
Frank has pointed out a small issue involving slope/intersection. It is just a small thing, however, and I've fixed it, for the most part, by slightly adjusting one of 2 separate 'effects' tab parameters(which one is the best fix yet, I'm not sure). It involves a dark outline, resembling a shadow at the intersection zone when close-up and when slope constraints are in place.
This issue can be easily fixed by lowering 'intersection shift'(a parameter that will not need adjusting when the shader is released, you won't have to worry about that) or, by reducing 'fuzzy zone softness'(in these images FZS is set to default = 1) in the same tab.
I mentioned this briefly a page or two ago here but I didn't think it was a very big problem.
I have got around this by reducing FZS by no more than half
or, by reducing intersection shift by a factor of 10, from '0.1'(the setting for these previews) to '0.01'.
Both methods fix the problem, I think I'll go the FZS way to finalize it, though.
Cheers!