-Do you refresh the view by clicking on the green checkmark (MEP view selection area).
=> Sorry, but I'm not sure I understand your request
-What do you call (activate another position) and how do you do it?
=> In a PEM of an assembly with configuration, right-click on the -> drawing view -> other position (snap as attachment)
And from there, you can choose from the configs of the set.
This makes it possible, for example, to have a cylinder in the retracted position displayed normally and in the extended position displayed in dotted lines.