Dragging a hot spot within the same page operates as always.
To another page in the project
The receiving page is selected and the dragged item is cut and moved from the original page and pasted into the receiving page. If the option key is down, a copy of the dragged item is pasted into the receiving page.
To another application
Hot spots are an internal data format and therefore are inaccessible to other applications.
From another application or the finder
Hot spots are an internal data format and therefore can not be imported from other applications or the finder.