This is how I do it.....
Click on "Objects" tab - upper left corner
Click on "Add Object" - upper left just below tabs
Two selections are offered.... object option will add one individual object...Population will add numerous objects.
To add numerous objects click on population at the bottom of the box...click TGO reader.
Your hard drive directory will appear...locate the TGO you want to use and double click it.
Two nodes are created in the upper left box....one object maker and one adjuster.
In the first one...object maker - click it.....towards the center is a distribution tab.
Below that is area center - three boxes at 0, 0, 0...TG2 loads all objects to the lower left corner in a very small area (1000 x 1000)...if your camera POV is in the upper right corner or in the middle of the terrain then you will not see the objects because they are over the hill and far away....so...
First increase area length to 5000 x 5000....the larger the size the longer the render time.
Now we need to move the objects where the camera or POV is....
Click on the camera tab - top middle
Click on render camera - upper left box
Go down to the center of that box and notice Position - click on the folders button to the far right of the three x,y,z position boxes it will say "copy coordinates or paste coordinates"
Click on copy coordinates and go back to the objects tab.
Click on "Objects" tab - upper left corner
Go down to the area center and click on the folders button and paste the coordinates
Now the objects are centered on your camera...half of the objects are in front of and half are behind your camera....adjust x,y,z for best fit.
Hope this helps...
Markal