Hi, I instaled corona version 1.7.2 as demo and I really like your software.
However I tried to make some new itoo forest object and even though everything is fine in viewport, corona doesn't render it. I have licenced itoo forest plugin version 5.4.0 and I can render it when choose vray as renderer. When I add edit poly modifier on forest object it can be rendered. I can render forest object merged from my old scenes. Also when I create new forest and choose preset from library, like some rugs I can render it. From which version Forest pack added support for Corona 1.7? There is only one version after 5.4.0 (5.4.1) with some bugs fix (my subscription has expired and I can't download it). With RailClone I have no such problems, except I can't use instancing engine if I want to use uvw XForm operator. I attached 3Ds Max file for easy understanding.
Edit: Sorry guys, my fault. There is a bug with rendering forest object for sure, but not new one as I previously sad. I upload new scene. With corona it doesn't render leaves on RC geometry, even though I add edit poly mod on it. With Vray everything is rendering fine. I tried everything in 3ds max 2018 and again same problem.