>When the "Show DXCC, grid and worked before" setting is selected in Settings-General, how does this show up in the Band Activity pane? I am not recognizing anything.
The next step is to re-read User Guide section ‘4.7. Colors’ and set/select colors as you wish see those Worked before. Of course you need to have those stations in your wsjtx_log.adi file (File -> Open log directory) and perhaps Rescanned in Colors tab.