Lowest-delay sections are drawn first, so the most delayed sections stay on top where lines overlap. A stop's dot is colored by its worst incoming section (hollow = no data for this selection). Click a stop or a section for details -- a click on overlapping sections auto-selects the most delayed one. Click a section in the list to focus just that one: its highlight turns violet, its start (teal)/end (orange) stops are marked, and a direction arrow appears along it.