Your problem is that the HDV codec doesn't works, isn't it?
That's nothing related with Prores.
Run Software update and see what you find there.
The set of codecs on your link clearly state:
"This update is recommended for all users of Final Cut Pro X, Motion 5, or Compressor 4".
Not sure if will help you or will screw things even more.
rafael
http://www.nagavideo.com