I have just upgraded to Win 7 64bit and have had a similar problem with getting "Camera Raw editing is not enabled" in Bridge
I had installed CS4 as a trial whilst I tested that my install of Win 7 was OK
When I activated CS4 I was using CS4 64 bit and never got the "I have deactivated the software from another machine" question
I tried lost of things to get Camera Raw editing in Bridge and all failed.
When I tried CS4 32 bit it wanted to activate the software - it asked the "I have deactivated the software from another machine" question and then rejected the activation as two PC were using the key.
I deactivated CS4 from the 64bit side and removed the key
Then I activated using CS4 32bit - all seems OK now
Hope this works for you
OSX Leopard / XP
Camera Raw 5.5
Here's a simple solution:
Open Bridge -> have any .CR2 image -> double-click it - it will open in Camera Raw ->in Camera Raw click on "Open Preferences Dialog" or Apple K, or Control K -> down at the bottom of a Camera Raw Preferences in the boxes "JPEG and TIFF Handling select "Automatically open all supported JPEGs" and "Automatically open all supported TIFFs" -> OK to get out of the Camera Raw Preferences -> Cancel out of the Camera Raw. Then close down Bridge and Photoshop. Reopen Bridge, right-click or double click on ANY image format (JPEGS, . CR2 depending on set Bridge preferences - I have mine set to always open in Camera Raw) it triggers Camera Raw from here on.
if you have any questions feel free to contact me.