How do changes in the culture and setting in the "voodoo Macbeth" adaptation affect the story?

The story of Macbeth as portrayed in the "Voodoo Macbeth" adaptation from 1936 was essentially unchanged. The setting of this famous adaptation was Haiti after the revolution that freed that nation from France, and this adaptation (which was directed by Orson Welles and produced as part of a New Deal initiative) was significant because the actors were all black. The actors were dressed in period costumes instead of Scottish garb appropriate for the original, but what was perhaps the most important change was that, instead of witches, Macbeth was advised by Voudou priestesses, whose prophecies were accompanied by drumming and other accoutrements of Haitian culture—or Haitian culture as the play's producers imagined it. The central themes of ambition, supernatural forces, and fate and free will remained intact—if reimagined—in a new setting.
http://www.openculture.com/2015/09/young-orson-welles-directs-voodoo-macbeth.html