When I try to show a slideshow in Impress I get a square white box filling the center of the screen with a small non-spinning hourglass symbol in the upper left corner. The right side of the slide shows from behind the box. This part showing is repeated to the left of the box. If the slide is set to fade in the the white box does not appear until the fade is completed. If there is no fade the slide pops in as described with the white box already in the center.
I am running Version: 6.0.3.2 (x64) of LibreOffice on a Windows 10 machine.