#1 create a new account with a node limitation to only view those nodes in question
#2 create a new page that filter based on node ID
I need access to create this for existing accounts so #1 is out.
#2 sounds good, I'm just looking for a bit more information on how to do that.
One option would be to create a custom property for the 5 or 6 nodes you want displayed in the All Nodes - Tree page. You could make it a Property Type of Yes/No. That will give you a check box to check in the custom property editor. Just check the nodes you want in the tree. Then your SQL query when you edit the All Nodes - Tree page would be custom property name = True. That should list just the nodes you checked in the custom property editor.
I don't think it's possible to show gauges in the Node Tree.
Hope this helps!