The error you are seeing is usually because the installer executable is corrupt or incomplete. I will send you a PM with how to download the SQL Doc 2.0 installer from our FTP site.
Regarding upgrading or evaluating a new product, if you have an existing version of one of our tools, you can run Help>Check for updates to download just the one product. If you want to evaluate a new product, you can contact email@example.com
and we can send you the mini toolbelt installer for just the product you need.
I hope this is useful information.