I get invalid archive too. This was because the transfer was cut off prematurely. I'll try downloading it again. Compressed files are more susceptible to corruption through transfer than other files and the server keeping the file can have an effect on the stability of transfers.
I'd like to stress that I've never ever had a problem with my own zip files using winzip. In fact in my life I have only ever had about 20 zip files go awry and they were ones I downloaded or were on damaged floppy disks (I have worked with over a thousand zip files in my life without problems).
So what's this "winzip has a high file corruption coefficient"? Maybe you're using an ancient version of winzip. I personally reccommend winzip as one of the best file compression utilities available.
In fact, I have so far had only 50% of my own rar files not go corrupt so I think the rar format is extremely lacking.
// Update: I tried again and it downloaded properly.
