Hi, please ensure that the buildings you're adding are "squared". You can do it by selecting the building and pressing "Q" on your keyboard. Thanks!

Sure thing! I used amenity=police here to indicate the approximate area of the District Police Headquarters. The "layer=-1" is just so that the end user can see where are they entering, whilst keeping all the features above. I don't know if that's how layer works, but that's just how I did it.