@dancetiger. After my update to 6.2 I also received the message that Halion was blacklisted. Turns out, it was only the VST 2 version. The VST Version 3.6.1 is up and running normally.
Make sure also to install the new Halion Library Manger (which is now called Steinberg Library Manager) in case you download the full content. SLM did not appear on my desktop by default, I had to search for it. After opening it, all libraries registered and when I opened Cubase, I did not manually have to search for them on startup.
I downloaded the full content and placed it in my current vstsound library. As has been noted before, there does seem to be some size difference.
Cheers.