[v6 General Discussion] Background slides

I have just tried to install ew6 on two different computers, everything works okay, but on the computer screen all the backgrounds are white. When I go live the projected image is fine, but I can't see the background on the computer screen. What am I missing?

Under Edit -> Options -> Live Options - make sure Alpha Channel is Disabled.
Yes, it's disabled. The images under media:images are showing, but under themes, they are just white. I removed all the themes, and re-copied them from the media:images and they are still white. They are white on the schedule, live, and live output screens too. On the projected output the image shows.

On my home machine this does not happen.

The only other posts describing a white screen are related to under-powered video cards.