Lost connection to Model Lib!?

Hi all…
Have any of you experienced losing “connection” to the model-lib in a scene.

I can see the Model-Lib, in the hierarchy. But I can’t see any of the objects inside in the sim - even thou I can see the placement-gizmo/dummy in the scene??

I have tried replacing the whole library AND tried exporting everything again from Blender… Still no object inside the Sim??

Hrmm… found a workaround - re-naming the model-Lib folder did the trick- But still have no clue why?!