All of the interaction with the weather routing system is done while the Weather Routing tool is active. When the WR tool is active, the lower portion of the sidebar is occupied with a set of controls which allows you to interact with the WR system.
You enable the WR tool by clicking on its icon in the toolbar:
When the WR tool is active, the system is able to display isochrones, isochrone segments, paths, analysis images and show text information related to the weather router. When you leave the WR tool, only the visible solution paths are shown (no isochrones, segments, etc.)
LuckGrib Weather Routing is currently only available on macOS. Support for iOS and iPadOS is under development.