Setting subpresentations/qml-streams to material textures doesn't work

Create a project with a qml stream and a subpresentation.
Create new material by pressing Add button on material inspector.
Add subpresentation or qml-stream to diffuse map of the material (before assigning the material to any object) -> Subpresentation is not shown set in the inspector nor is it saved to materialdef file.
Change a color of the material -> Now the material is saved. Supbresentation set previously is also saved, but is still not shown on the inspector.
Assign material to an object -> subpresentation preview is shown on scene view but diffuse map property on inspector is still empty.

If presentation is added by dragging to a material on timeline, then inspector shows it. However, if you press save, it is lost, so apparently it is not actually saved to the materialdef file.