I think that the green line will only show up when you are moving - stop and the green line disappears. In an ideal, obstacle free, world your green arrow will match the black arrowhead pointing to the cache as you are moving.
As a follow up - Is there any way to get distance to the cache on that navigation screen?
Greg
You are correct. The green line shows direction of movement. But the compass should rotate regardless of me standing still. It should rotate as i rotate. Correct?
To get the distance to cache, you need to press select and there is an option (don't have the unit with me now) to customize the 2 fields at the bottom of the screen. Press arrow key to select a field and then arrow key to select what info to display. I always put distance to end and speed.