Hello

Can someone describe, in some detail, what the navigation marker and the super marker are used for in TWOS with real navigation enabled?
I'm a bit lost as to what they are for.
Thank you!
Also....since I'm here....
Do you guys go throughout the sub on your first mission and "talk" to the guys and/or try to raise their stats? Is this some sort of way to level the boys up? It seems I have the ability to raise some stats during first voyage. Does the dialog trees have any positive or negative effects?
And......I try to update the sunrise times and the board goes completely inaccurate. Known bug?
Again....thank you