Glad you like the rotating parts. There is a play/pause button as mentioned in a post above that will stop the animation so you can place more parts. The animation is in play mode by default when you start a new ship or start modifying an existing ship.
Also, though it may be my imagination, it appears as though once you actually build an animated ship and it's on the map, the animation speed is 1 tick higher when displayed on the main map, than it is in the shipyard.
I thought I noticed the same thing too. I will have to look into it to see what's going on there as to why it looks faster.