Hi BODN.
I was able to install the content via an old installer of Nuendo I had (which I also own). I can’t guarantee this will work, but try these steps:
-
Go to Cubase 10.5 Updates and Downloads | Steinberg and download the very first full Cubase 10.5 installer from November 13, 2019. It’s down the page a little. Download the one that says FULL INSTALLER. This should theoretically include the 3.0.23 Library Manager because the broken one (3.0.25) wasn’t released till this year.
-
Uninstall Library Manager 3.0.25 (if you’re on Mac, drag it out of your Applications and into the trash - you can’t just install the older one on top of it). Then install the 3.0.23 Library Manager instead.
-
I don’t know if this step is necessary but someone mentioned it in another thread so I did anyway: open the 3.0.23 Library Manager and have it open when you’re installing Cubase 10.5 (in the next step).
-
Install Cubase 10.5 with all its content using the legacy installer you downloaded in step 1. Hopefully (fingers crossed) it will install all content using the older Library Manager.
-
Update Cubase to 10.5.11 using the smaller update file available in the Steinberg Downloader or on that first link I posted.
Good luck, and let me know how you go!