Thanks for the feedback and encouragement! I'm trying to organize a tutorial for this.... Another day of tweeking and a few more tiny lights go off in the brain where I feel like I almost understand the tree modeller. It *is* sort of like shamenism afterall! ...Or gambling. The numbers aren't absolute, and the worst part is that the advanced settings are not recorded by Carrara's UNDO, so you gotta remember what you changed and by how much..., while you wait for the tree to recalculate..., and then wait for the preview to rebuild....