In a last desparate attempt to get running again, I left the InstallShield uninstaller at the ‘staled’ point of removing shortcuts. After a little over half an hour, the state changed and it completed. Not sure why it took so long, but today I learnt that perhaps I’m not as patient and I thought.
The only other point to note is that the new installation appeared to be incomplete, but going through the InstallShield ‘repair’ option sorted that out. I now have a working system again…
Hopefully the above will help anyone who experiences similar. Be patient…