I have seen some tours have a static background image with active loading text above. I have a large background image I wish to display while the tour is loading, its a big project and currently I just see a black background.
Something I have done, have your "background" image be a hotspot. Size it dynamically so it just covers the window. It will actually cover and hide the pano until it is loaded. Set an onloadcomplete event to remove the "background" hotspot.