Hello,
D5 render is an awesome software for architecture renderings, i really enjoy using it.
I would like to suggest an option that could maybe help other users as well.
When using the outline mode, it could be good to have the opportunity to exclude grass, trees and specific objects from being outlined, because in some case the outline just turn all the object into black, due to a lot of lines being to much close to each other.
You can try outline mode with grass material in 4k you will just have some black area in the ground. You will have the same effect if you have some vertical elements in an interior design, if these elements are not large enough and spaced enough the hole thing will turn to black.
Thank you for your efforts making such a great software !