Welcome:). Here's what Nero has to say about SCSI Target Errors, which is not exactly your 'unspecified target error'.
Your error code is 05 / 27 / 00 = WRITE PROTECTED. Not sure how that figures into it...
The media you are using, POMSC001, is not a MID that is known as 'excellent'. It may work fine with your desktop burner(any Kprobe scans to prove it? ), but I think your Sony DW-D56A doesn't like it. I would try better media first.
You could try updating to the latest firmwareif you haven't already. Your edited error log doesn't specify what version you have.
You have ??? in your error log at the bottom where aspi drivers are listed. You might try installing an ASPI layer if you do not have one. Your layer should be listed in the nero infotool near the bottom, along with nero's own ASPI layer. The layer is not needed in winXP, but sometimes it helps.
There is also the huge Sony DW-D56A to look thru... :eek:
Keep us updated on your progress as your solution may help others