Hi @Anonymous User,
From the video I see that you already checked the layers and also graph networks visiblity is on, so I suspect that the UI did run into some issue. But its hard to tell just from the video what went wrong.
What version of CE do you run? Does selecting work after a restart of CityEngine or just reopening the scene? Does ist work in other scenes? Can you check in the Log (Windows -> Log) if there are errors around the time the selection started not to work anymore.
Best,
Jonas
