Hi,
Thanks for provided screenshots. Just one additional question. Does this problem appear while rendering locally or by using network rendering service (distributed rendering or backburner)?
Could you please send us the VRay log file (VRayLog.txt) to support@itoosoft.com? Or feel free to send us your copy of the scene and we´ll double check what's causing it. In this case, please use a web sharing service as 
WeTransfer. Thanks in advance.
Regarding the object color in 
Points-Clouds mode:
Usually, Forest gets the color used for 
Points-Clouds mode from the 
Diffuse slot of used material. This can be changed to 
Use Color ID - this way it´ll use the 
Color ID of the item from 
Geometry list (so you can modify it's appearance easily).
Kind regards,