Bug fixed.
Please update Real World Terrain through a built-in update (Window / Infinity Code / Real World Terrain / Check Updates) to the latest beta version.

The tree placement looks like it is fixed. Thank you for the quick response.

We have extend the list of OSM tags to generate grass.
Please update Real World Terrain through the built-in update.
After that, clean the OSM cache (Real World Terrain / Clear Cache).

I checked out your coordinates.
Grass has three locations (img1).
Trees are not marked in Open Street Map.

I am unable to get grass to generate. I check the Generate Grass checkbox and add a grass texture.

What might I be doing wrong?

My info is: <Coords tlx="-94.96272198496092" tly="39.39589998817443" brx="-94.87311474619139" bry="39.22642529111295"/>

And I am using Arc GIS imagery.

<Coords tlx="15.842446302810686" tly="50.204403882401934" brx="15.874117826858537" bry="50.18731573232694"/>

Perhaps in your area grass and trees are not marked on Open Street Map.
Please open www.openstreetmap.org and check markup of your area.

Or perhaps the camera is too far from the terrains, and you just do not see the grass and trees.
Zoom in to the terrain, to check it out.

Or write to us the coordinates of your area, we will check it.