Group Editing is a feature of the CTC Editor that allows you to change certain items in the same way for any number of objects of the same type. It also offers you to manipulate things in a comprehensive way, which makes it much easier to accomplish certain tasks, rather going into low-level editing which requires a deeper understanding how things work and interact in CTC. So even if you select only one object for group editing, it is sometimes better to do “group editing for one” then do the low-level editing where you may have to go through several panels to accomplish the same task.
Group Editing can be invoked from the detailed list panel (menu item “Edit” → “Detailed Lists” in the main panel – see here for further details) – this panel maintains a selection list, where you can add or remove any objects of almost any type. Depending on the view you have, objects covered by the view can be “group edited”, and if you have at least have one meeting the view criteria in your selection list, the “Edit Selected” button is enabled.
For further information on the available object types, the group edit panel and what you can do there see