So, I found a solution now, after contacting the support:
The support suggested the following:
- Close all programs.
- Open the ‘Run’ command prompt and press the Windows logo key + R simultaneously.
- In the command line of the ‘Run’ window, enter this path: %appdata%/Steinberg
- Locate the Cubase folder which is named the same as your version, for example 'Cubase 11_64’.
- Rename it (for example to "x_Cubase 11_64”) in order to hide it.
- Important: If you find folders of previous program versions, make sure to hide or remove them too.
- do the same for the HALion Sonic SE folder.
I di all that and started Halion Sonic SE Standalone and it did work. I could select all content again.
BUT: When I started Cubase and added an instrument track with Halion Sonic SE all content was blocked again.
So I deleted all content of this folder “%appdata%/Steinberg”
I deinstalled all Halion content and programs.
I removed all Halion content from the Steinberg Library manager.
Then I re-installed everything again.
Now it works again as it should.
All content in Halion Sonic SE is selectable and working again.
Be reminded, that by deleting the content of the folder “%appdata%/Steinberg” you will lose your custom preference like shortcuts and you will have to activate Cubase again, if you already on Cubase 12.
Hopefully, this will help others with similar problems.
Regards
Maik