Also I'm still waiting for answer to my flagstick questions. Think most are 7 feet, except wicker baskets being 6 feet?
Well Jim answered this about the time you were posting and I too, believe the normal flag sticks are nominally 7 ft tall.
The big rectangular box is called the "aimer" and it is nominally 10 ft wide when you are on the tee and seems to be a bit larger from off the fairway. The triangle is ~3 ft wide from the tee.
When putting on the green, the aimer is about 8 inches wide and the triangle is ~3 inches wide. If you line the edge of the aimer up with the stick, the point is about 4 inches off hole centerline, and if you line up the up/down triangle within the aimer (elevation arrow) with the stick (or in the middle of the IN or FT), the point is about 3 inches off centerline. Edge of aimer box lined up with edge of hole is a little more than 6 inches off center (since hole is nominally 4.25 inches in diameter).