I’m getting this issue now with UE 4.10. I have a custom asset viewer (very like the static mesh editor) with a slider in a toolbar that, when the value is changed, creates a new static mesh from the custom asset. The resulting static mesh is then set as the new preview mesh via the same kind of flow as the static mesh editor setPreviewMesh. In doing this, the slider stops sliding and I have to click in it to get new values rather than sliding. Do you have suggestions as to how to handle/debug this issue? Note, if I don’t rebuild the mesh, the slider works just fine. Except, that nothing else happens, of course.