UK Kalender's main window shows the application menu and toolbars, a view of the cuurent month and the saved events. 

If you want to add a new event to the calendar you have to choose a category, write a description and some notes and customize the event display and reminder. 

In the Repetition tab you can set the appropriate repetition rate and modify some additional conditions. 

The Action tab enables you to select some actions to execute for the selected event. 

The View menu allows you to select the view type and lets you move to another page. Also, you can choose the toolbars that you want to have visible in the main window. 

The Extras menu gives you access to some additional features of the application, including Categories, Database, Holidays, etc.