Thank you for this ressource MostHost_LA, that’s interesting.
In my situation I can’t actually use this, because I couldn’t remove a portion later with this system.
Here is where I am at with my system ( just did a simple wall for now) :
When i’m building, there is a ghost appearing from the last spline point to the cursor, and add the portion when I click.
Now I need to learn how to set material to each portion.