Hi JoshDNoble,
There could be a problem with the downloaded file, you can download http://trials2.adobe.com/Applications/DesignPre/CS4/Win/ADBESTDSCS4_LS1.7z
Extract it using winrar and then install it.
Download winrar: http://www.win-rar.com/predownload.html?&L=0
Click "download winrar".
Revert in case of further issues.
Thanks,
Atul Saini