You can generally make changes to your design, even your structural design, after the project proposal, except regarding damping devices. Damping devices must be approved by us based on your damping proposal submitted by the damping proposal deadline (see Section 7 of the official rules). The damping device, if approved, has to be exactly as shown in your approved damping proposal. However, you can choose to not use a damping device even after submitting a damping proposal, but then that means you won’t get the corresponding bonus as well.