6.7 reset my preferences and it was a pain to get them back. I use camera faithful almost always since it is suppose to be how the colors are actually rendered and doesn't have other saturation and contrast added by the profile. I use the others very sparingly. I recently purchased the upgrade to lightroom 4 and use that exclusively now. I always preferred ACR, but the updated develop module in Lightroom 4 is great and seems to work best for me. You might try the trial if you don't already have. It is about 1/2 the price of lightroom 3.
Hopefully the problem gets fixed with your new download and things go back to normal. Good Luck!