I read through the first half of this chapter very confused. I thought it was going to be a lesson on writing macros when it was really about the built-in macros that Lisp comes with. The first few paragraphs gave an introductory explanation and so I kept reading the chapter as though it was trying to teach my how to write macros, not how to use the IF, WHEN, and COND macro. Once I figured that what was really going on I quickly re-skimmed the chapter and it made a lot more sense :)
Not sure where the error is but the symbol "�" showed up a handful of times in the online book.
LOOP looks very interesting. As long as there is a cheat sheet I can get at while learning the different ways it can be used it looks to be a nice tool for making code easier to read.