I think the problem is that you're not considering the actual implementation. For example, let's say you want to make a house. You need to place down 4 floor props, 8 wall props, and 4 ceiling props. You need some kind of "ghost" to work with while building in the building mode, otherwise it'd be impossible to do it properly -- you wouldn't have snapping and wouldn't be able to see what you were building around if parts immediately disappeared after placing them. Or is the idea you had completely different? Is it that you request your settlement builds a concrete wall and then, after a delay of x hours, it's available in the build menu to be placed freely? That was the other guy's idea, not mine. My main thing is I want the construction of a windmill for example to take say... 12 hours (not final value) i.e... I build a windmill then 12 hours of in-game time pass. Just something as simple (is it?) as that would do it for me for the foundation of a mod like this.