Hi,
this is a special case - the images were loaded as hotspots and the progress bar will shown only for real pano images,
showing a loading bar or text would be possible, but a bit tricky - the "onloaded" event of each hotspot could be used to increase a user defined loading counter variable, and then this counter could be used to scale and/or mask a loading bar or to calculate a text and show that...
best regards,
Klaus