1. Go to 3D Scene > Camera tab
2. Select your default camera.
3. In the Camera animation section, make sure the Enable checkbox is marked.
4. Close the 3D Scene dialog.
5. Connect 3D Scene > Out-ports > Mouse Events > Mouse Release
3D Scene > In-ports > Camera > Set "name"
Done! As soon as the user releases the mouse button it will trigger the Set Camera in-port.
You might want/need to set the speed for the animation Camera animation section.
Was this what you had in mind?