Full-screen gray version of the map; no top bar or nav bar. The side panel shows the ship's current route, its range, and the port it starts from.
Click ports in order to add waypoints; a side list shows ports in order plus estimated travel time and distance for each leg and the full loop. Legs through a canal add the lock time (6 chambers × 3 s through Panama, not counting any wait) and show the toll and XP bonus: "to Balboa · 44 nm · 30 s · Panama Canal: toll $4,200, +50% XP".
Rules: consecutive waypoints must differ; since routes loop, the last waypoint must also differ from the first. Every leg, including the one back to the start, must be within the ship's range.
Ports the ship can't reach from the last waypoint (or, before any are added, from the port it's docked at or heading to) are greyed out; clicking one explains why. Out-of-range legs show in red in the side list.
Buttons: Cancel (always available), Undo last waypoint, Accept (enabled once 2+ waypoints and the route is valid). Each stop in the list has an X on the right that takes it out of the route (and one of a pair of the same port left side by side).
Assigning a new route to a ship at sea: it finishes its current leg, then follows the new route.
Assigning a route also un-pauses the ship.
A ship docked at a port that isn't on its new route first sails to the route's first port (a normal, paid leg).
Running ships leave a port when their port stop ends (and they have fuel for the next leg); paused or route-less ships stay docked.