A Note to Vista (sufferer...uhm..users)! Vista protects you from downloading these harmful EXE files with improper certificates by going through the entire download process then deleting the files if you don't run them immediately! I just tried to get the Bryce content and gorilla and they both never appeared on my USB drive.

To get these files, download to a place with lower security settings (Desktop, or Games) where write protection is turned off. Once on your machine they can be moved to another directory or drive.