Cubase 12 won't load Halion symphonic Orchestra

My Mac was running Cubase 12 and HSO quite happily until a couple of months ago, until my hard drive crashed.
After re-installation of everything Cubase now cannot find Halion symphonic Orchestra files.
I used the Download Assistant to redownload HSO, but I can’t find out how to get the downloaded files in a position where Cubase can see them.
Can anyone help?