Cannot see world in layout generator view

(WM Pro 3019)
I have a graph starting with a heightmap (file input). When I use a layout generator whose input is connected to some node far inside my graph, i don’t see any world in the layout view. If however I connect the startup heightmap node to the layout generator, I can see the world properly in the layout view. This is a problem because i want to see the altitude of some feature in the layout view after erosion or other nodes, and I just can’t !

Update: actually even when connecting the input of the layout generator to the startup heightmap, sometimes it shows an empty world. I don’t know the conditions to come to this situation though. Restaring World Machine fixes the problem (but not when layout node is connected to nodes far in the graph). This may be a bug I guess…

So I realized the "world’ we see in the Layout view is actually the one corresponding to the node currently selected on the left side of the Layout view, where we have all the nodes in a list. However, when i select some nodes, even though they are previewed in the 3D view, they do not display in the layout view. Why? Is this a bug?