If magic zoom and other stuff is visible on the 6d screen depends on the status of the "info" button.
Every time you press the "info" button, you see more or less stuff on the display.
This also works without Magic lantern, you can see a histogram and level meter etc...
Magic lantern can only put stuff on your screen if you have no "standard Canon" stuff in on the display, push the "info" button as many times before you see magic lantern stuff in the display, for example RAW histogram or battery level, or magic zoom (push the magnify button).