Weis,
rar files are like zip files, it is a compression format so the files are not so large to download, store, etc.
You can get the evaluation version of the winrar software here:
http://rarlabs.com/rar/wrar36b5.exe
or another software tool that is "free" and manages the rar format as well:
http://prdownloads.sourceforge.net/s...2.exe?download
Also, many times the "free" downloads only allow one connection at the time so you have to wait for the first download to complete before initiating a second download.
Try it like that and see if it allows you to get the other files.