I do know a lot about coding and you usually would take out all those portions from the core app and then add them into your modular expansion packs (aka dlc). This to me look alike they did last minute blocks in a full game that IF they did remove them from the core would break the core. This is probably due to the way the engine is running. In the glitch videos you see all the detail including pipes and wall braces etc i.e. the engine really creates a real world for the physics to work off of (a wall needs exterior material like brick but also needs studs and what not to build the frame). So taking out kings cross section at last minute might have literally collapsed the buildings in the rocket yard. Easiest to simply add a lock (invisible wall made to look like doors) and open it with a dlc. 9.5 mb is only big enough to contain scripts and metadata/configs.