If you are having problems running the boot camp installer in Windows 7 RC1 x64 edition or any other Windows 7 release, x32 or x64 thees Tips & Trix might help you get all the drivers installed.
First of, make sure you have your OS X installer DVD or CD that was delivered with your Mac.
Insert the CD or DVD and close the auto run dialog if it pops up.
Now, go to the windows explorer, WIN+E keyboard shortcut.
Navigate to the drive where you have the Boot camp files ( like D: or the like ).