cokbun -- Can you elaborate? I don't understand what you're trying to say. As seen in the video, the statue floats and does not touch the tile to weight down the see saw on one end. Once the statue is floating, it does not 'collide' with anything. So, you can't 'float up' along with the statue as some kind of hack. Anyway, more words please.
update 1:
OMG! It worked. I started pushing the statue next to the blue slime. If you keep pushing towards the "fence" as if you're going to fall off the floor, you'll float up to the next several floors. On the upper floor you'll stop eventually, but don't let go of the statue. Keep pushing towards the "fence" and you'll reach the floor with the latter. Now you can let go of the statue. Thanks, cokbun. This looks like a good work around to this bug.
update 2:
I've finally made it to ken07's location. I get the exact same problem. The character will drop through the black part of the fake, half-circular town. Normally, after making a circle around, the game changes the appearance of the town structures. Unforunately, as you can see in ken07's video, it seems like pcsx2 can't handle whatever it is that square/enix programmed for this puzzle.
update 3:
Well, I managed to perform a complete circle even though there's only blackness. The game 'loads' the next phase of the decaying city. When you drop into this new 'level' it shows the complete circle. The black spot is gone and you no longer fall through the floor. But it looks like this also breaks whatever script that allows the next phase to load. So, you'll end up running in circles without any changes to the level.
update 4:
video of workaround: