Try, try again.
After breaking the setup my Processing for Android installation, I opted to rip out the Android SDK, rip out Processing, delete all remaining files and folders and environment variables.
I then re-installed Processing and let the fresh Android Mode install the Android SDK (rather than hook into my own installation).
A little wrestling with the permissions on the sketch for the camera and I was (finally) able to get both my front and my back camera running on my Samsung S2.
Now we are away with modifying a bloggie lens to sit on the phone and to use the processing unwrapping of the bloggie image to knock up a collision sensor.