The Symlinks I did after the stated problems occurred by research in Google & trying any fixes I assumed may solve the issues changing from alias's.
I can use Logic as before but I have to have everything performing as specified. As an engineer in multiple disciplines if something is not correct I have to fix it NOW.
These problems point to missing graphics & associated links & miss-reporting of libraries that are clearly there and controls that are greyed out, I assume because of lost connections.
My dilemma is it's all there, but Logic doesn't know it.
My last Logic update was to the latest version 10.4.8 on 11/01/2020 which worked fine for a few days.
As a complete anorak everything must always work as expected.
DB