QU: Is there a way to 'transfer' (copy/import????....) my user db files to my sitewide setup?
Yes, just copy bayes_*.
cp ~/.spamassassin/bayes_* /etc/sitewide_bayes/
Make sure no SA processes are running as you do it. Autolearning, etc could cause inconsistency between the toks, seen, and journal files when you copy (note: the journal isn't always present, that's fine). When you copy, there should not be any bayes_lock files, as those should only exist when a SA process has the bayes database locked and is actively writing it.
