I tired to drag and drop my KML file onto the CesiumViewer with FireFox (version 39.0). All geometries can be displayed, however they were wrongly rendered with white color.
But, everything works fine in Google Chrome.
The weblink of the CesiumViewer which I was using is:
My KML file is available via the dropbox-link below:
I'd appreciate if you could look into this issue.