Each alert / alarm event is displayed on Alarms Panel as follows: Each Event Preview tile shows a thumbnail with the first frame of video footage for the relevant event; the playback button; time stamp of the event and camera ID.
When you hover over the Event Preview tile, all information about the alarm pops up.
If you click the button, the event footage / alarm recording will then be played back in Event Preview in a repeating cycle. To stop playback, click the button.