Bon ben je viens d'avoir un retour du support de skalp……… pas de solution……..
"You can select everything and choose from the context menu ‘Reconnect to Model’
Element which are changed will stay ‘red’ and need manual intervention. We can’t change this because the SketchUp API doesn’t give us methods to do this."
Si quelqu'un a une solution alternative, je suis preneur…..