I am not able to reproduce the behaviour you are experiencing. The installer downloads fine and launches without getting the damaged disk error. Have you tried downloading the installer again? Please delete the file you downloaded and try to download it again.
I have downloaded installer over 30 times and deleted it each time. I still get the same message error. I even thought that OS X 10 might be the problem, so I reinstalled Maverick. Nothing seems to solve this problem.