I believe I've discovered the reason why the file wouldn't upload.
One of our members at our forum also encountered this issue, and it would appear that security software on the server was preventing the file upload from completing. It blocked the file because it had a specific PHP function in it (
base64_decode). That function was part of a commented-out (inert, not running) block of code, which I have now removed.
Try re-downloading the zip and re-uploading the file, it should work now
Fillip