I am testing the scatter system and I found out that if I use a scatter created by Alpha 7.2, nothing will appear on the render. You can see the objects in the viewport being scattered on top of the surface, but when you press render nothing appears.
Also the settings used in a previous corona scatter are used when you create a new scatter. So, if I changed the Scatter count to 10k, when I create a new scatter, this had already 10k as a Scatter count.
Plus there is that issue that if you change the map used for the Density using the compact material editor, 3ds max will simply freeze.
I am using:
3ds max design 2015
Build timestamp: Jan 29 2015 23:52:46