I am using spire version 2.8.66.
Diagrams which have been edited with spire will no longer show an excel window when you try to edit the data behind the diagram. Excel does appear in the taskmanager, but no window is shown.
I have attached an example project. The template has 2 diagrams. The project will insert data into the first one, and leave the second alone. After doing this, the first slides diagram will no longer be editable, while the second will remain editable.