I haven't tried Nero with any setup, but packet writing should work from any shared CD-RW drive (packet writing -- not session writing or disk at once writing) since packet writing works much like writing to any drive. At least this does work with some older Adaptec DirectCD 3 software (only installed on the PC with the CD-RW) and shared to the network like any other drive.
That said, the Adaptec DirectCD sofware has never worked well for me (or my CD writer for that matter) on my Win2000 and PC hardware platform, so I would only run something like the DirectCD software from Win9x/ME, which all work great with it.
Of course, with DirectCD, you are limited to UDFS formated CD's -- usually CD-RW CD's and not CD-R although both may be possible.
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You know, I would think that you would not want to write CD's across a network since network congestion, throughput and other issues may affect the CD burning. It would make sense to burn full CD-R's from one PC only, have an input directory on some LAN shared drive or NAS, then copy the data from the LAN share/NAS to the local drive before burning CD-R's. Otherwise, underruns may occur.
Just a recommendation.