It is very easy to use Zip/Unzip function on the Web Client, and Wing FTP Server also supports Zip/Unzip On the FTP Client side, just use the following commands:
SITE UZIP filename.zip
SITE ZIP filename.zip sourcefile1||sourcefile2||sourcefile3||...
If you want to unzip a file "test.zip" in the current directory, just send a raw ftp command "SITE UZIP test.zip".
If you want to compress files "test001.jpg", "test002.jpg", "test003.jpg" into a zip file "myphoto.zip", just send a raw ftp command "SITE ZIP myphoto.zip test001.jpg||test002.jpg||test003.jpg"