I have run across a few bugs with Vue Pro 6.6 update when dealing with Eco-Systems. 
     - Removing Eco-system layers does not remove the plants from the terrain.
     - Distribution maps do not map the same in all layers.
     - Eco-systems in mixed materials with a function for the distribution of the two materials sometimes bleed over to the other material.

But everything else seems to be working well. It might be because I updated to 6.6 before I upgraded from Vue 6 Esprit to Pro. But when I downloaded the Pro update, it was the same file, same size...