I find that the touchscreen is not that sensitive on my Nook Color that is running CyanogenMod 10. I know this is not a hardware problem, but a CM 10 software problem because the touchscreen is fine when I use the default Nook OS.
Some of the problems I face are that certain areas of the screen are highly insensitive to touch, sometimes the touch is registered a bit below the region I am touching and sometimes a touch is not registered at all.
One feature that has helped my touch experience with CM 10 a lot is turning on the Show touches feature. This shows a white circle wherever the OS can sense your touch. With this feature turned on, I can see exactly when and where my touches are being registered on the display by CM 10. And when I see that my touch is not registered, I can safely try again to touch that region.
To turn this on, open the Settings app and first turn on Developer options. Inside Developer options, turn on Show touches.
Tried with: Nook Color 8 GB and CyanogenMod 10-20121228-NIGHTLY-encore