Panosphere Overview window seperated from the content
This affects at least the newer OS X builds by Harry van der Wolf:
When I click the 'pin' icon to have the fast preview's new panosphere overview in a separate flowing window the 'Overview' window is seperate from the content (the actual panosphere). The panosphere stays in the lower left corner of the screen while the empty overview window can be dragged around. It will stay on top of every other hugin window and eventually hides the panosphere. Zooming the window (i.e. dragging the bottom right corner) also zooms the seperated content.