Ok Romantique Tp , so…
It didn’t work 
I eventually hunted down Cubase 6 - which is the only installer with the HSE Pro & Artist & EXP libraries 
for some odd reason these are not included after ver6 
The sound files are in the proper content location folder, but I still am unable to see them via Mediabay or HSse3
I tried reinstalling both HalionSonic 3 and HSse3 - no impact. 
NB for those thinking that this a tiny nuisance - the real annoyance is when auditioning midi loops in MediaBay and it defaults to a particular patch, e.g. modern elec. bass - which used to be in these libraries exclusively. A work around would be to assign all these loops to the patches now available in the latest version of HalionSonic or Halion. Not a small feat though… 