typed:

I have a CDRW which triggers the "calibration area full" error in Nero
5 consistently, even after a "full format".

Obviously all burning attempts also failed (cannot perform end track).

The drive is a brand new Gigabyte GO0404 DVD burner, while the CDRW is
a relatively new Verbatim 24X CDRW.

Does it mean the CDRW is destined for the bin?

Did you try with different media? it could be that drive can't calibrate
itself succesfully,so it can be dead.