After Effects camera tracking - change points


I am trying to track a camera in an aerial scene. I want just to put a circle on the ground, but for some reason AE only tracks points in the distant hills and next to none on the ground. It also seems to think the hills are the nearest to the camera judging by the point marker sizes.

Is there a way to tell AE to exclude certain parts of the footage, to include other parts in the calculations, or does anyone know of a tutorial for a similar scene which does not use the automatic camera tracker?

I tried to use Blender and while it seems it could work like I want it to it crashes when I press the analyze button or stops tracking - decides at random with heavy preference on crashing. The other post is at if anyone has any idea what is going on.