It's difficult to say exactly why your StealthCam didn't take any pictures. The cold may have affected the batteries or your camera. I have a StealthCam and it sometimes makes me scratch my head in warm weather as well.

I have another homebres style camera that sometimes gets some moisture in it and will freeze and not take pictures for a day or so and then start taking them again once the sun warms it up enough. I opened this camera up one time and it had ice in it and it was still working.

I checked my cameras yesterday after they had been out for six weeks in temps as low as -10 and the camera took a picture of me. It is a homebrew with rechargeable AA Energizer batteries and had taken 150 pictures before I showed up.