Hi, this seems to be the same issue as reported for PHPZip here:
Grandt/PHPZip#4
Other tools, such as Archive and even "unzip" via terminal, can open the zip file with no dramas - it's just the Archive Utility built into OSX that has dramas.
From the discusion:
The root cause is a mix between an odd behaviour of the deflate
algorithm in the PHP implementation of zlib, and a bug in the Mac OSX
"Archive Utility"
Has anyone else encountered this?