Why is this a critical issue and what exactly is broken? There is valid image data on your LiveView, the interface looks normal, so nothing looks broken to me.
You're right. This doesn't have to be a critical issue. But, one major point of Magic Lantern is the revamped video interface and the things that go with it. There is no point of me having Magic Lantern if this part doesn't work.
Let the user guide and the menu help be your friends.
I looked at the user guide to try to fix this. It said to make sure that LiveView is enabled, and it still has no hint of Magic Lantern in the LiveView.
@a1ex what do I do to fix this?
I'm pretty sure a1ex can only see the back of his eyelids atm. An excellent opportunity to re-read the user guide, and pay attention to the menu help.
If all else fails, delete everything on the ML card, and copy the contents of the nightly build to the card.