Hello Dirky Wechsler. Please try to use the XWidget's "Options" (right click on icon tray) and see if can use an option from there.
Also the ALT-F4 is the known command for close the open windows ONLY! I recently discovered that you can even close a widget with it, but if you use this feature better change the combination! Rarely use this command for the windows so I had no problem with XWidget..Maybe the Developer can disable this in the next version... Please add the same post to "Bugs & Feature Suggestions" section.. It will be usefull..!
After you add a widget on your desktop you can remove the widgets with right click on it->close or when the widget's bar is open (when you double click on the icon tray) press the "X".
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