My problem with the Manaan starship hook was that once you change the layout to "Centerpiece Cross A", you can place one centerpiece deco immediately, but if you try to select one of the other centerpiece hooks, it seems to select one of the smaller inner hooks instead, making it impossible to place more than one centerpiece.

The hooks at the front are visibly bigger than the building they are placed on, but you can't click them from below. So I tried to elevate my character somehow and found that the "Memorial of the three" (possible some other large hook decorations as well), placed on the nearby large hook, manages to provide that elevation.

It still takes a little clicking around to catch the centerpiece hooks, but at least I managed to put 3 rockets up there.

https://i.postimg.cc/6QH39vFd/Screenshot-2020-08-23-09-23-46-634316.jpg

https://i.postimg.cc/3xFNc6Bf/Screenshot-2020-08-23-09-21-25-350178.jpg