There is a problem with grass material. The material extends and contracts along the element boundary in form of rectangular shapes. Attached screen shot illustrating the problem. A number of users have also indicated the same issue on Bentley Com...

Lumen is great for generating quick renderings however complex. While in concept design phase, In creating a plan view it tends to distort at some point because there is no toggle on/off perspective view. The same goes for elevations and sections....

We are planning Lumen RT Central Dashboard to view all models from 1 location