On mapboard 5, does hex E07 have LOS into hex E05?
I think yes because the centre point of hex D06 (which defines how the hex is treated for terrain modifiers) is a road hex and thus has no obstructions, but that protruding corner of the stone building into D06 bothers me somehow.
On general principles, any bit of art of different terrain to the centre point of the hex it's in has no effect on LOS through that hex, right ... ?
(like small stands of trees, sheds and so on)
Line of Sight is calculated from center hex to center hex. Hex terrain is determined by whatever is beneath the center point of the hex.
Thus artwork in the edges of a hex have no impact on LOS calculation or terrain type determination.