The history panel displays recent look ups and all cluster spots in list form with a thumbnail of their QSL picture if available, the call sign of the reporting station, if you have worked this call in your log the information will display in Green as well as giving the date and time worked. (Note: if you have enabled the Show Bands by DXCC check box in the Lookup Prefs then the information will show in Green if you have worked this DXCC entity before).
If an alarm was raised by this spot it will be shown in Red, a manual lookup will show as Blue and your QTH will show in Grey.
Double clicking on the text portion of an entry will display that QSO and tune the radio to the QSO frequency.
Double clicking on the Flag or QSL Image portion of the entry will display the Flag or QSL Image full size in it's own window.