I have had some difficulties in chapter 5, with shadow-cljs It has some project dependencies that are in your examples, but not mentioned in the text. Also, when I tried running the shadow/demo example the compiler complained about react not being found. Fortunately, this was a different problem from what I was getting, so I managed to piece together something that worked.
But, I need to add this has been a great book. Hard work for a newbie like me, but I am learning tons.