Sorry for dumb question, if it is ))) I'm kind of new to TG. Using it for just couple of weeks.
Thank you again. Seems like i managed this out with your help. I used a surface layer with no restrictions, plugged in merged pyramid of four Fake stones shaders and different Distribution shaders with Terrain/Texture and Terrain settings for altitude and slope restrictions respectively, as a mask for each Fake stone shader. That seems to work generally, stones are distributed correctly and shaded quite properly... But there are still artefacts on some stones. Very little, but still. And they seems to me even scenic. I suppose it's for severe deforms of surface before with no smoothing on at stones layer (i read that from honored Tangled Universe, don't ask me )) but i really want to leave them that way with smoothing off). So i consider the problem solved. Thanx to all ))
PS: All surface layers like soil, grass, etc are before stones in node chain, after stones there are compute terrain and layers that must affect stones, like wetness, etc. If this is important