GE 6.6.0.0 on Windows 10 x64. Whenever I click the gear icon on the GE titlebar to bring up the settings dialog, the dialog appears half off screen (the OK and Cancel buttons can't be seen). If I drag the dialog sideways so that it is completely visible, click Cancel to close it, and then click the gear icon again to open it, it appears where I last positioned it, completely on screen. However, if I close GE, open it again, and click the gear icon again, the dialog again appears half off screen.
I've written numerous Windows programs over the years, and I can assure you that it's trivially easy to interrogate resolution and monitor information to ensure that dialogs/windows appear *on* screen (GetSystemMetrics, MonitorFromWindow, GetMonitorInfo).