Paul,
i think i just found a bug, i have an stadium with more then 65000 animated people, forest tells me that the display limit has been reached but that it will render fine or i can increasing the limit in the display dialog, if i don't increase it, max crashes at the end of the render but if i increased it it works fine.
this is in max2016 and vray 3.20.02
Guillermo Leal.