In order to get automatically calculated lap and segment times based on GPS recording / imports, you need to have a track with a proper GPS configuration.
To create a track, go to 'New' on the first tab and on the top right select 'New Track'. Give your track a name and set the track's type of soil. If you are currently on the track, simply select 'Location' to be located. Otherwise you can either enter the GPS coordinates or search for the track by using the input field. Then save the track.
On the same view you can configure the track for GPS use. To do this, select 'Track Setup' and follow the instructions or watch the tutorial in the video down below.
You can also configure the track after recording or after an import. There you'll find the same 'Track Setup' button. You have the advantage that your lines are overlaid on the map, which will help you to set your finish line and segment markers a lot easier.
Before you start a recording or import data, you have to select the track on which you are riding / you rode. After recording or importing the GPS data, lap and segment times are then calculated automatically.