It is still a galton board, no doubt about it, and any good comment has a LINK, so you know, i really dont know what you are talking about, and if mine is bad, you make one, it'll be the exact same as mine.
i think if it isnt csg or wat kilinich said, its obviously a polygon that was drawn in such a way that it created a small line that you cant really see, like maybe say, by not closing the polygons edges before finishing it, or your mouse fell off the table... or... something...