Comment 2 for bug 510284

I backed up a couple of screens and was able to complete the install via the "use the largest continuous free space" option during partitioning.

Manual partitioning was impossible. would not accept a larger /boot partition, would not accept a 10G / partition type Ext4, nadda!

Also: Taking the "use the largest..." option, it did not offer to migrate the user settings from the Windows Administrator account. Ubuntu usually makes that offer, which I skip.