I figured this one out. I have been using Camera ICS+ because I think it's a better camera than the stock Motorola one. But I couldn't get it to come up on the lock screen. The reason was I had never set the camera to be the default one because I never needed to launch the camera other than through the home screen. What I did was to launch the camera from an icon in my gallery app (Gallery ICS for those who are interested) and it gave me the option to launch the stock camera or Camera ICS+. I chose Camera ICS+ and now it shows up as the camera on my lock screen. Hope this helps someone else.