The service is available in the "Utilities" menu under the Sunrise / Sunset item.
Select the location on Google Maps and the date on calendar. The system will automatically calculate the data.
The Maps will center to the coordinate set in "Set preferred position" field in the "Anagraphic Data / Preferences" page.
The calendar will initially propose today.
The "Time Zone Offset" is that of your computer, such as the local time is your time zone.