Popup notifications do not work for me either. Status is online and I have "Show pop-up notifications when: [There is an incoming call] enabled".
All other notifications appear to work, the only time I see any kind of notification is if the app is both visible, and the app is displaying the settings pane. Otherwise when the app is in the tray, I get no popup notification that there is an incoming call. Because the PC headphones are not being worn all the time, and the app is minimized, the only way to know that there is an incoming call then is to enable the ringtone in the PC speakers.
I also cannot figure out to show the right hand history pane either. The only way I can trigger it is to call the softphone and then click on the flashing incoming call notification.