Hello,
I'm kind of confused as to how that error message would show during the install process. That file is only loaded once the site is installed. Please be sure that you are installing the site shaper into an empty folder. We have a full video tutorial explaining the entire process on this page:
http://www.shape5.com/joomla_tutorials.htmlAlso, I have verified the downloads and the file mentioned in the error is in the downloads.