May have missed it, but can't seem to find a legend/key to the icons on the right side of the screen for the Briefing: Thanks!!
Here are the diagrams from the manual, all manuals can be found in *Your Steam install drive letter e.g. C*:\Program Files (x86)\Steam\steamapps\common\RailWorks\Manuals\EN (other language folders are present you need to check your own localisation if not English)