Re: Leap installer - is there anything that actually works in openSUSE?
640x480 is an occasional consequence of multiple GPUs, especially in laptops, or of a GPU that's newer than the distro. Are you using an Optimus laptop or multiple GPUs? If so, appending nomodeset to the installer command line may produce an acceptable installation environment.
Repo errors like yours sometimes happen because of a mirror that is out of sync. Usually those will resolve by trying again after the mirrors fix themselves, sometimes in just minutes, other times hours or next day.
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