I'm pretty sure there's more than one way to skin an Aslan.
And, there probably are a variety of ways to artificially create gravity, using gravitational based technological devices.
However, the simplest concept might that that the gravity tiling just makes objects fall towards it, interrupted by the floor that it's embedded into.
Classic had the gravity trap, which I can't figure out whether it meant all floors had it, or was specifically placed in certain areas, where, I suppose, localized gravity could be increased upto six times (I would suppose based on the preference for six in the game), and reversed ceiling direction.
If the effect created is just falling, the ceiling doesn't need corresponding tiling.
And, starship designers aren't likely to want more expensive gravity tiling, if all they need is to recreate a Terran norm gravity for human passengers.