I never used magic lantern before so I don't know if it's normal but if you're in live view and you access to ML menu, if you don't touch anything the live view appears for less than a second every 6 seconds. The magic zoom has a flickering of strange colors and image deformation every now and then. Then I download the previous version, 2017Oct02, and try the magic zoom with fullscreen mode and didn't work. I didn't try this with the last version.
Issue #2842 duplicate