It should be under the AccessPoint tab in the QvWS section that you point out in your post. The tab will be disabled I think when you stop the QvWS Service so try starting it, adding a checkmark to the checkbox and applying your settings. Then you can stop the service again and the download link should be there.
What the checkbox does is add the following entry to the config.xml file for QlikView Web Server under C:\Documents and settings\All Users\Application Data\QlikTech\QlikView Web Server (or C:\ProgramData\QlikTech\QlikView Web Server if running Vista/Windows 2008 Server/Windows 7):
This is added within the <AccessPoint> section but before the <AddCluster> part. So you can add it manually too if you'd like.