When designing a rocket I'm frantically clicking away, trying different parts and ripping them back off. And so it happens that sometimes I accidentally rip off parts of a carefully staged asparagus design. Placing the parts back on the rocket in exactly the same place, and having all the fuel lines and struts back in the correct position takes more time than it should. Sometimes it just works, sometimes it just doesn't want to fit anymore. Therefore I would like to suggest these small improvements: Escape key cancels the current action and returns the state just as if I didn't rip the rocket in half Undo and Redo buttons and shortcuts (Ctrl Z, Ctrl Y) Thank you!