Hi there! My office window faces east and this morning, your map showed shade from the building across the street (correct), as well as shade from my building on the lawn below my window (incorrect).
"Below canopy" - what shadows would look like on the ground. If you're in a dense forest everything is in shadow because the trees obscure the sun. I guesstimate how big and where the below canopy shadows land. Any vegetation that's more than 2 meters tall, I place a shaded area beneath it. Not super accurate because it treats trees like cylinders instead of a sphere/triangle on top of a cylinder.
"No trees" - only building and terrain shadows are shown on the map.