Nero Cover Designer Calibration Not Working

I have been noticing lately that the labels are printing slightly out of alignment. I originally thought this might be due to switching paper stock, even though the Meritline website says this one is identical to CD Stomper. However, when I print a Calibration Test Page, it is indeed off by about 1mm. (I don't know when this happened. It used to be right on the dotted line!)

Anyway, I made the change to the horizontal offset, but it still prints out 1mm off the center on the calibration page! It's like the setting does nothing. Has anybody else had similar calibration issues?

I suppose I can try a diffent sw app. But, I've already got NCD, I'm used to it, and don't wish to change if not absolutely necessary. Any suggestions would be greatly appreciated. (Please avoid the "don't use sticky labels" debate, and try and keep it to calibrating NCD.)