For whom it may interest this was my solution
In July after a motherboard failure, I was obliged to re-install Cubase but started from my Cubase 5 install disks and should have started from my Cubase 6 install disks. Today I only took the Halion Sonic SE for uninstall then re-install and after, its content installer from the same Cubase 6 DVDs.
That remedied the SE situation now Im getting all the instruments.
