To avoid confusion about what kind of viewer, xml v swf, lets just re-track.
It is a Flash based programme, it used to work in Opera after checking the box in UserPrefs to 'Allow XMLHttprequest', it doesn't anymore.
Since Opera updated, I couldn't find the exact same worded UserPref 'Allow XMLHttprequest' so maybe the one I checked is not the right one. I was hoping someone who understands UserPrefs (not me obviously) could tell me which UserPref is the one I do need to check to facilitate the interactivity of these files as it did before.
Sorry to be a pain. This is the only reason I got the Nexus 7. The virtual tours are part of a service I am licensed by to provide as a Google Trusted Photographer. I figured that a 'Google' Nexus would probably offer most compatibility. And indeed it did for around 9 months.
I can make the tour in either swf or html5(xml) (I do both for webpages, so that they suit many browsers and devices) if this helps you to guide me to a solution. Of course they work both on-line and off-line on PCs and Laptops.