I'm using Panotour 1.8/2.0 to create iBook Widgets as well and from what I can tell, based on this section from the Kolor wiki there are no plans to implement the iBook Widget functionality from 1.8 into 2.0.
The exact quote is:
For compatibility reasons and because of the complexity of Panotour virtual tours, this feature is not available anymore in Panotour 2. Instead, you can consider using HTML Books
That quote from the wiki links to this forum thread that offers a workaround using the HTML Books app. Now I haven't bought the app yet (it costs .99 USD) but based on the description in that thread and reading about the app it doesn't seem to do what I'm looking for.
I don't simply want to be able to view a PanoTour on my iPad, I need to be able to place the widget into an existing book. We purchased this software for this reason in the first place so I hope it's still possible. I may buy the HTML Books app today and see if I can get some sort of workaround going.
To update, I have downloaded HTML Books and the app does what it says and seems to do it well… only problem is that it downloads the resulting iBook into HTML Books not into your iBooks library. As a result I can't get to the iBook that's been created in order to unpack it and pull out the widget. I have emailed the author of the application to see if he has any insight on to how to accomplish this.
I do wish that they just had the iBook Widget functionality in PanoTour 2.