I have just finished working the last example in the book and all challenges. Now I know how little I know…
I must complement the author on avery informative book with broad scope. Well written too. I only had a few problems.
In chapter 15, page 218 where a modal sheet with a callback is used I found that the application crashed.
I found this to be because the sheet was created autoreleased and was released as the event loop terminated. This was fixed by a simple retain call and release in the callback. However I have not seen anyone else report this problem so maybe I just did something wrong.