This may help someone.

I am now on my third iteration of datasync. The last one (0146) kept on failing to work properly (the connectors would not start and I got Python errors in engine.log when trying to log in as my admin user)

I uninstalled and reinstalled via YaST (remove add on/reboot/add the addon etc). This failed to cure the probem on three attempts.

Today I ran the routine (/opt/novell/datasync/), rebooted and reinstalled by adding the addon and using exactly the same configuration as before. This worked.

I have also noticed a few other changes since the re install - notably my SSL cert for the Webadmin has reverted back to the self-signed one.

I conclude that ds_uninstall is a "more complete" uninstaller than simply add/remove addons in YaST.