Apologies all.
It seems I was a numpty and should have double checked. There seems to have been a delay between me changing the settings on the BIMServer and what the User was able to do. We discovered today that the changes I had done to the BIMServer had in fact worked.
So nothing to see here, move on....
AC versions 3.41 to 25 (UKI Full 5005).
Using AC25 5005 UKI FULL
Mac OSX 10.15.7 (19G2021) Mac Pro-2013 32gbRam AMD FirePro D500 3072 MB graphics