Originally posted by ali_warchild
overcoocked save is corrupted
Did you extract it from the RAR?
Also, when making your own ZIP, make sure you are making a ZIP out of the CUSA folder, not the "Overcooked 100%" folder. If Save Wizard sees the latter in any form, it will think it's a corrupt save. It can only see the CUSA folder, and the save files inside, and if you are doing the Import method it can (and must) also see the ZIP containing the CUSA folder and saves. No extra text or other folders.
Note that I'm only taking guesses based on a quick look at the download.