Hey Kobra,
I extracted download to desktop, then using my ftp client uploaded it (initially) to public_html directory on my server. I was trying to figure out how my ftp program worked(with no help) . No subdirs were uploaded at the time. On the next ftp run, I loaded it to shop dir.

The cart works fine from what I can tell in the new dir, but when I removed the cart file from public_htm dir. My site went down. Did the script reset something? My main pages use htm/html extension with php calls inserted in the coding. these calls don't work the serve just adds it to the file output for the browser.

And yet zencart runs fine in a sub dir.. I just don't get it.
I noticed that it changed/added stuff to htaccess file, which I replaced and removed excess coding, but still same result.