It's set in the texture itself, not in Shader Forge

Try setting the texture to clamp instead of wrap

Sort of, yes, if you mix around with the Ztest / Depth test setting, you may be able to achieve what you want. But it often requires multi-pass settings, which you can't do in SF. You can, however, have two meshes in the same location, with different shaders.

There's no built-in node for it at the moment. I recommend either generating it offline, like you mentioned, or use substance designer either on its own or in combination with SF. It's quite expensive to do real-time noise on the GPU. There is an example on the wiki on how to do that though :)

Marking this as solved, it really should have been on the latest version :)

I can see that happening - thanks anyway!

I've got that covered. I just need time. Do you know someone who manages time? :)

You should be able to drag the substance-generated textures into Shader Forge authored materials. Or does it not work?

It's not a Shader Forge specific issue, it's an issue with alpha blending in general. I would suggest doing additive blending or multiplicative blending, if it fits.