Try one of the camera replacement apps in the market or take it back to a Verizon store and get it replaced again. A refurb is supposed to be CLN (Certified Like New).
I've used Pro Zoom Camera 5X for years and it works well for me. I've tried Vignette and Camera Zoom FX. Both of those get good reviews and have been recommended previously on different forums. They both worked well on my phone but didn't seem any better than Pro Zoom and I'd already paid for it. So, I stuck with it.
Right now I'm using a rom that has the Atrix camera built into it and it's working great for me.