@dsemikin, links are all fixed now. Thanks for finding them.
With respect to your questions:
the Markdown and Latex versions of the book - are they synchronized? Are they supposed to have the same content, or are they going to diverge?
They will most likely diverge. The goals are different in that the markdown version is designed to provide an interactive, platform friendly version of the book, whilst the LaTex version provides a publication quality version of the book as a PDF file. The LaTex version is the most up-to-date. One day there may be scripts to automatically update the markdown version from the LaTex version. Something for the future.