Check your play disk for dust, fingerprints or scratches. If it worked before in the same drive, then there is something interfering with it now. Make sure all background programs are shut down, as well.
Look at the manual install procedure in the troubleshooting post. You should only have to try manually extracting the file you get the CRC error on (it sounds like the install keeps going after the error). Even with the full manual install, it is basically just extracting a few files to a couple folders.
