Book excerpt: Back in 1969 when Morocco's ancient capital was a hashish clouded happy mecca, Crosby, Stills and Nash recorded their cheesy (and hopelessly inaccurate) foot-tapping anthem 'Marrakech Express'. A generation on, award-winning journalist, author, and one-time glamrock fan Peter Millar uses what is now the country's best visited tourist destination as the embarkation point for a literally reverse-engineered train journey through this still exotic, diverse and challenging North African country, struggling to maintain its unique blend of tradition and tolerance in the turbulent winds of the Arab Spring.