In one drawing only the "glass sliding doors" showed transparent. All the other "windows" and "french doors" showed solid. I had to replace all the windows with sliding dooors and adjust the settings to make them appear as the windows I wanted. They were all the same class and fill. I have tried setting the windows to be "no fill", but no luck. I have also set the wall to be "no fill" but this makes no difference.
Are there any absolute settings which have to be activated in order for the glass panes to show transparent?