A single hotspot, taller than it is wide (234 by 259 pixels), sits right of center and leads to Demo 4. Without the picture it is impossible to say what it covered. The shape suggests a panel or column rather than a button.
The frame above is drawn at the original proportions. Each dashed box sits where the 2009 hotspot sat and links to the same screen it did then, so the tour can still be walked end to end.