Hi Klaus. More intense testing on that link would show you the error case. It doesn't happen every time. It depends on how long you waited to click on the button that makes Iframe visible.
As when defined hidden Krpano is starting. There are lot of code behind on autorun="onstart" so it takes some time (menu is automatically generated based on how many scenes project have and many other objects)
So, when code start to use stagewidth or stageheight and their sizes are 0 or NaN (also don't understand why stageheight is NaN) as Iframe hidden it make problems in starting all elements.
I tested startup with checks to determine if Krpano is started in hiddne Iframe (0 NaN) and stop proceeding unit onresize show screensize >0, but I was wondering is there any other better workaround to somehow stop Krpano to start while in hidden Iframe? Somehow autorun="onstart" not to be triggered until there is known Stage size?
Do you understand the issue now? If you click on button
Link very fast you will see that onstart action show some size as there is a size if the iframe. It is understandable that Krpano don't know if as its "parent" Iframe actualy don't have its own size but I was expecting Krpano not to trigger onstart or preint actions while in limbo. It cound be kind of improvement proposal as why would Krpano start when display area not visible or defined.
Cheers