I however have to specify that the virtual visit is integrated (joined) into Joomla.
When the same virtual visit is realized with the option to incorporate all the data then integrated (joined) into Joomla it works.
If I do not incorporate the data then it is the display (posting) of the first photo which bug as indicated in my first message. I also observe that if I put the same on-line virtual visit but not integrated(joined) into Joomla the visit works but before the first view(sight) displays all the virtual visits which establish(constitute) the virtual visit disentangles on the screen some fractions of a second.
I also tried (not incorporated data) an export without incorporating files xml. The bug is the same. There also files xml indicated as not being found are nevertheless present in the corresponding file.
With my webmaster we also visited the forums joomla but unsuccessfully.
You have answered your own queston.
I seem to remember that I've read elsewhere on other forums - but can't recall where and when - that entire tours must be in a single file if run within Joomla.
There may be a way around this but I know nothing of Joomla.
I would think it best to seek help on the krpano forum:http://krpano.com/forum/wbb/index.php?l=2
You could also seek help on the panoguide forum:http://www.panoguide.com/
This thread may be relevant and one poster on this thread claims to be a Joomla expert so you may be able to get some useful info from him?:http://www.panoguide.com/forums/qna/8347/