I'll try to cover all your questions:HERE
is a CR2 RAW file from on of the pictures.
I always shoot in regular RAW mode, 21MP.
Tried to reseat the CF card without success.
I get the same bad result when shooting with EOS Utility (transferring directly over USB).
The lines do not appear in live view with 10x magnification for some reason.
The point is that I can see this pattern in 100% view on most pictures and even after saving as JPG. This is really annoying. I just want a nice 5DII to shoot with, but not something like this.