Adam, when I came to page 216 and typed in the body of the method:
- (void)windowControllerDidLoadNib:(NSWindowController *)aController
XCode marked ‘tableView’ as undefined. I’d started chapter 12 and carried on with it into chapter 13 with a copy of the RaiseMan project obtained by following the main text in chapter 8, rather than a copy of the project of challenge 2 of the last-mentioned chapter which is where the tableView instance variable is introduced.
I think you need a note on page 216 which asks the reader to add ‘IBOutlet NSTableView *tableView’ to ‘@interface RMDocument’, and to make the necessary link in Interface Builder.