1. That depends on how many such "nodes" happen to be present in the scene. The user will load a scene with a map, which is made up of 0 or more nodes and/or edges.
2. Only the user can edit the node locations/orientations through this menu (at least as I envision it now).
3. Probably not applicable due to 2., but in such an event, yes.
This might make things a little more clear. The entire widget for editing nodes looks like this. The upper scroll area is the one I'm concerned with now:
WholeGUI.png
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