The question is, how do we move a filer from one NT domain to another, and still have Administrator access to it afterward?
Place the "NEWDOMAIN\Domain Admins" global group into the filer's "BUILTIN\Administrators" local group (you can use Server Manager to do this). You might also want to take a look at the filer's /etc/usermap.cfg file. It will probably contain an entry of the form:
olddomain\Administrator root
which you could change to:
newdomain\Administrator root
You should then be able to "cifs setup" the filer into NEWDOMAIN, and have at it, administratively speaking.
Keith