Indesign objects cannot be added to CC library

we use a a CC library in Indesign CC22 Mac with various object types in our company.

It seems not to be possible to add frames/groups from Indesign by drag and drop or otherwise into an existing library any more (within Indesign and its CC Lib panel)

Editing assets by duoble click onto the assets doesn't work eather...

I the CC Lib app I can drag and drop assets as .idms files onto my desktop - but importing it his way leads to an error message about unsupported file types...