Hi Ricardo,
Some examples such as example3D are meant to be experimental, so I moved them a bit far away from main examples.
Additionally, we deprecated position: and it took some time to update examples, but now they should work :)
In order to connect elements with lines you would need to use BlLineElement. Corresponding examples can be found in Bloc-Examples-Line category.
In attachment I send a short video showing how lines behave when anchor elements are dragged/resized.
P.S. Just for fun I also attached a video of example3D. It is nothing special, just shows how to integrate OpenGL in Bloc. During esug Ronie told me that using UFFI-OpenGL is not the best approach.