as mentioned above I tried a new database and had the same error, so I think there is something wrong with what I'm doing rather than the export/import.
Just had a play around with it from home, and it seems to work from there.
I can now see all the data and link it - yay!
I get a different error from here - now when I try to share a layer to the database I get error: Relatio "mfd2880_data does not exist; error while preparing parameters."
Looks like maybe the imported roles don't have permissions to make tables on the new server?
I got the same error trying to share a table to a new blank database with the postgres user on this system though.
Going back to the work machine I still get the same error there. So I can share drawings from that machine, and read them from the home machine, but I can't read on the work machine or share from the home one!
Home computer is also 8.0.30 but enterprise edition, not database administrator. Accessing the database via a VPN. Also is Win7, work is Win10. I might have to try another machine at work.
There is something funny with the imported login roles, pgadmin4 doesn't display any permissions for them or allow them to be edited.
Just tested the home computer with the our old enterprise database, and it fails trying to share to that too.