Please note that these bushes and shrubs only work by corona scatter. if you want to use them in vray you should scatter the twigs on your mesh with another scatter plugin like forestpack.
There are four corona scatters with four different types of leaves.
It works so easy, make every model with every shape you want, choose your desire corona scatter and select your mesh as distribution surface. that's all, no need for UV map no need for changing corona scatter parameters (although you can change them for different results).
make sure to uncheck 'Renderable' for your meshes.
No matter the dimensions of your mesh or how many meshes you add for distribution surface, it works fine.
Vray max file of twigs(leaves) in the archive.
You can see examples of different meshes in fourth, fifth and sixth renders.