In V1.007 we added a new FPE field which did not exist when the Veg Pack was uploaded to the store called ANIMSPEED. Fortunately you will also find this field in the entity properties of the tree, which should be set to zero (or 100). You can add a value of 50 to half the speed of the tree and 200 to double the speed of the tree. Bear in mind that when you have a speed different from the default tree entity, it will CLONE rather than INSTANCE the tree and thus cobble more system memory. You can create your own custom tree but copying the entity and it's related files to a new folder in entitybank, then modify the FPE by adding ANIMSPEED=25 to create a tree moving four times slower than normal, and when you use that you can keep with the better INSTANCE approach and avoid manually changing the animation speed in the editor itself.
PC SPECS: Windows 7 Ultimate 64-bit, Intel Core i7 920 (PASSMARK:5008), NVIDIA Geforce 9600 GT GPU (PASSMARK:752) , 6GB RAM