I have just installed the Nightly Build onto the 5D MkII. Can see the functions but when I press the button to go to shooting mode the error 'Error 30' comes up and tells me to either turn the camera off and back on or to remove the battery and put it back in. Only removing the battery and putting it back works, to get access to the functions again. Shooting seems impossible any which way. I take the card out and the Error 30 still appears when I press the shooting button. I tried reformatting the card in the camera but still it kept the Nightly Build. But in any case, card or no card, my camera seems affected. What is the best thing to do in this case?! 