I finally got Ch.11 to work. For some reason I had ‘arrangedObjects’ not only bound to the content of table view but also to ‘selection indexes’. This caused a run time crash whenever I clicked the ‘add’ button.
As soon as ‘selectionIndexes’ of the NSArrayController was bound to ‘selectionIndexes’ of the table view everything worked
Since one can easily miss a connection or make a mistake binding elements I would suggest to include a picture of the NSArrayController bindings at the end of the chapter for people to use a reference.
… binding ‘selectionIndexes’ of the NSArrayController to the tableView really necessary? I experimented with that setting and apparently it also works when ‘selectionIndexes’ is not bound.