this has very slightly helped me, but I am still clueless.
I am not facing another problem that I just can not figure out.
I have a 1x1km terrain which I am scattering rocks on. In the middle of a terrain there is a road. I am using open spline area to exclude rocks from being on the road, and also scale exclude falloff to make rocks gradually larger from the edges of the road.
What I need to do now is to have another area, larger rectangle, which makes instances less dense and larger towards the edges of the rectangle, so that I am able to render the huge scenes. If I had same consistent density across the entire 1x1km terrain, i would run out of ram.
But here is the problem, the falloff properties are global, so I can not have my road scale falloff and another, much larger scale falloff towards the edges. Every day, I am more and more surprised how cumbersome and inflexible forestpack is.