Groove Agent 4- installed kits are not visible in mediabay

Only 3 of 10 installeds kits are visible in the mediabay (groove agent 42.30.320).
I did a clean install of Windows 10 (with all updates) Cubase 8.5 and Groove Agent 4 (with all updates)
All of the content (GA4 and other kits) is installed on a separate drive.
Only Fusion essentials, Jazz essentials and Colliding Worlds are shown.
All of the other agents are invisble. Only when I rescan the other styles are visible (but greyed out).
There is also no “All Instrument Sets” menu item.
Loading kits via Load multi program lead to an error that says the content can’t be loaded because it’s created with e newer version… etc.
I removed GA4 and its default content end re-installed it.
Nothing changed.
Uninstalled GA-se, GA4 en re-installed GA4 again.
Nothing changed
Moved all content to the original path C:\ProgramData\Steinberg\Content\Groove Agent\VST Sound.
Something changed. When I load multi programs the kits load correctly and will play. But loading via the mediabay is still not possible.
What’s goning on?!?!

I’ve also had issues with Colliding Worlds. I couldn’t find it in Groove Agent 4, then I realised it was visible in Groove Agent SE. This appears to be a bug with the installer.