How to display a node to extend a capella element?

Hello,
I am trying to create my own Viewpoint in Capella Studio.
It should behave at first like BasicPerfo, that is to say that some nodes should extend Capella elements, as shown below :
I thus tried to start from the BasicPerfo source code to create what I want (I did not find a way to open the BasicPerfo viewpoint as an DSL project in Capella Studio, so I rewrote all the code by myself using the generation feature. I have implemented the OpenAction method the same way as it is done in BasicPerfo, and BasicPrice).
However, the node that I am trying to display and link to a Capella element does not appear on the diagram when I try to use the OpenAction. It appears in the .melodymodeller, nonetheless.
Do you have an idea about why it could behave like that ?
Here is how the node is described in the diagram vpdsl. I do not clearly understand what “provided-by” means, and neither how to implement and use a query. So this could be the issue…
Thank you all for your help !
Have a great day,
Antonin

Goal_from_BasicPerfo.PNG
Node_description_BasicPerfo.PNG
Goal_from_BasicPerfo.PNG
Node_description_BasicPerfo.PNG