Hi Bill,
Just tried this and seems to work fine in non-demo version. I think this is related to the fact that in demo version tree view can have a maximum of 20 nodes. You will get a message once notifying that 20 node limit was reached and after that it will not give you a message anymore and just won't add any more nodes. Schematic view, similarly, can have a maximum of 7 nodes, and there can be a maximum of 3 views open concurrently.
Marsel Khadiyev (Software Developer, EPHERE Inc.)