TL:DR yes there is a seal along the roof edge and alignment poles/rods so things stay flat.

I do fire suppression builds for these tanks, so all of my equipment on the tank lid has to move up and down with it as it gets filled/emptied. So we end up with self coiling cables/hoses that have to collect themselves on the lid as it fills up. Linear heat detection wire goes all the way around the rim of the tank and also along the lid, which melts and signals the alarm/suppression system in the event of a fire. Companies with more money also have us install UV/IR based flame detection.

Same with these usually having a ladder that becomes more or less stairs depending on how full the tank is.