From what I've gathered on this forum, the "ice walls" keep everything on Earth. Having no gravity, the only thing that keeps us grounded is the Earth's propulsion upwards. Rotating the Earth on any axis other than it being outside of the "ice walls" would mean that the ground would, at some point, be angled to a point where we'd fall. Then maybe we'd roll continuously until we hit the "walls." Rotating more, at some point, the Earth will be upside down. I can use upside down correctly as a term here, because if the Earth is flat, we're obviously on the upper side. If not, we'd fall off. How does one stay on an Earth with no gravity if it's rotation turns it over? The Earth's upward movement doesn't keep us grounded if the flat ground we stand on is upside down. If anything, it would pull the Earth from us. Tell me if I didn't make this clear enough.