The first sheet contains an overview. You have the option to select a year, date and color. Days with many "events" have a darker color, days with less "events" have a lighter color.
The window to the right shows all events for the selected day. Double clicking on a month takes you to sheet "Month". Double clicking on a date takes you to sheet "Day".
(Click to view a larger image)
You can quickly jump between months and years using the top two rows. The first four "events" are shown in each date. Select a date and all events are displayed in the window to the right.
Double clicking on a date takes you to sheet "Day"
Here you can select a date in the top right calendar, you also select an hour and the corresponding event is shown in the window to the right.
Double click an event and you will be taken to sheet "Table" and the corresponding row. Likewise, if you double click an empty cell, a new row is created with date and time, see picture below.