Hi. Today, I purchased the CS5 Standard for Mac and dowloaded the 4 files that were on my page. One was the full version, the other three were described as "additional content" like new fonts. The full version installed fine, but the other three will not install. I get the error "invalid checksum" when I try. Is this because the full version already includes these? I looked in Illustrator and did not see the fonts listed on one of the three files.