You are really starting to worry me. I've had a couple of different peeps online check and they can all download the ones you've mentioned with no problem. I really think you need to either check to make sure you have the most up to date version of your browser and that you are running a relatively up to date version of winzip or that your windows has the right accessories installed to be able to open zip files correctly.
Yes, I'll try to download them again tomorrow.... I have probably a problem....