Windows 7 has a different folder structure. You will have to report this to Daz and wait for them to give you a fix. That is if you can not create a dummy folder set up on your desktop and install there.
If you try that just make sure you have the runtime setup inside your dummy folder.
One of the reasons I left Daz was because of their installers.
What happened to good old fashioned drag and drop. :-)
Regards, Tom