Hmmm... interesting log. Are you sure the ZIP archive got downloaded completely? It should be 52 654 442 bytes long.
Anyway, in AmiKit you can try to unpack the ZIP archive to RAM - in name mode simply drag the archive file and move it over the RAM icon. The ZIP will be unpacked there. Then go to RAM:AmiKit_UPgrade1100 folder and copy Expansion and S folder to AmiKit: and reboot. The update should be detected and installed.
Just make sure you backuped your AmiKit installation first (maybe I should write it first ;)