Fixed THZ2: Sad Underbelt

[Liliam]

The underside of this conveyor belt is a bunch of tiles instead of being another conveyor belt scrolling in the opposite direction. This is especially aggravating because I distinctly remember a section in the old Specials Reference Document (this thing was like the bible before the wiki existed) that mentioned this very use case:

533 - Scroll Ceiling Texture and Carry Objects

For conveyor belts on the top of FOFs, or for conveying items on a ceiling. Tag this to the FOF control sector and give the FOF control sector a type of 1024, Conveyor Belt. For realism you might also want to scroll the control sector's floor texture in the opposite direction (see linetype 510).