Light times are used to set the times and colors for day/night cycle.

Cycle Time - total day/night cycle time in seconds
Start Time - The time from the start of the mission to begin the cycle
Start of Day - the start of the day according to the game
End of Day - the beginning of night according to game
Start of Sunrise - starts blend of night to day
End of Sunrise - finishes blend of night to day (building lights deactivated)
Start of Sunset - starts blend of day to night (building lights activated)
End of Sunset - finishes blend of day to night.
Seasonal Shift - based on spring/summer/winter/fall. Don't worry about this ;)

Fraction of Day
Ambient Color - set ambient rgb value
Sunlight Color - set sunlight rgb value
Fog Color - set fog rgb value