There are 2 SAP notes speaking about this issue.
1825684 - nZDM: No data maintained for remote database connection
1713021 - nZDM/Portal: Core service [tc~lm~nzdm~crrsrv] does not start
I believe you have gone through both of them. (Not sure whether they are relevant in your case)
As you have done a system copy did you do an export and import of the Java schema ?
Regards
RB