When you create a new scene, you have an empty timeline. Unless you are assembling from an EDL or importing a Wiretap timeline, you must manually create a new cut.
The Save button is for saving editorial changes to a currently loaded cut.
If you want to create a new cut, you will need to click New.
To create a new cut:
Click Editing, and then click Browse to display the Browse menu.
Drag source clips from the Browser or Library and drop into the Storyboard or Timeline.
Enter the name for the new cut in the Cut Name field.
Click New.
A new cut is created. The name given to the cut appears in the Cut Name list.
To create a new cut version or to save a cut with a new name:
A new cut is created from the current timeline. The new name given to the cut appears in the Cut Name list.