Event lines can be toggled using the icon on the Rendering toolbar or using the "Toggle Event lines" action.
The Color of the event lines can be changed in Preferences -> Appearance.
Several things will happen when event lines are enabled:
1. Arrows will be drawn to all action targets for currently highlighted item in 2D modes:
2. Order, in which patrol points and interpolation points are connected will be shown in Classic and Visual modes:
3. Corresponding Polyobject Start Spots and Polyobject Anchors will be connected in 2D modes.