I'm running Vista and downloaded the IWDNPC_v1.zip file. When I try to open it, it shows the two files (install app and readme) but doesn't allow me to open/run either. When I try extracting using Windows Explorer, it doesn't copy anything to the destination folder. When I try to copy/paste with Windows Explorer, same thing: doesn't create a copy.
Found a solution:
1. Right-clicked the Zip folder, clicked Properties, and clicked the "Unblock" button at the bottom of the General tab. (Not sure if this is necessary, but I did it as part of the solution.)
2. Extracted files using WinRAR.
I was able to successfully extract using WinRAR. Not sure if this is just a unique quirk of my machine, or if it's a Vista issue, but wanted to pass this along in case anyone else runs afoul of it.