Also after crashing and restarting Unity, a couple times I've had to reimport the shader I was working on (got this warning):

A default asset was created for 'Assets/Shaders/myShader.shader' because the asset importer crashed on it last time.

Sorry it probably wasn't clear that the image I supplied was the (yes, old!) example I was following (while using the latest version of SF). This wasn't a screenshot of a node network I'd created, but one I was trying to recreate. I'm using SF 1.26 and Unity 5.3.4.f1. I've since been using different node networks but still getting crashes.

This needs to go in the wiki as it worked for me, and it took me ages to realise you can in fact use terrain normals with SF, despite the wiki saying you can't.

I've just installed SF from scratch and I'm getting similar, repeated crashes.

For me, Unity crashes along with Shader Forge, I just see ShaderForge "saving..." as Dale's screen above, then Unity dies. It'll happen when trying to open SF, or when trying to hit play.

Have mostly been playing around with distance alpha fading as per
but plugging the distance stuff into alpha so that terrain which is far enough away will fade into the distance.

I'll make some changes in SF, hit play, reopen SF, crashes.

I've saved the error logs/crash dumps if that helps? All I saw that made any sense was:

"Enlighten scene contents: 0 geometries. 0 instances. 0 systems. 0 probe groups. 0 cube maps. Scene is up-to-date.