@Kyronix Maybe you can tell me if this is intended. I raise the floor tiles to make a roof to the maximum allowed height. No exploit involved to raise them higher than allowed. All my roof tiles disappeared. They were even with the top of the craftable walls. Or to make it more clear you were able to walk off the roof cause there wasn't a wall lip to stop one from doing so. My plants, teleporter, and light house stayed but the roof tiles split town. It seems they were legally placed but they're gone now. Why?

To the OP it's the same with flowers/plants also. They will fall under the floor regardless of how high the floor is, doesn't need to be a maximum height or whatever. Same fix. Raise them a notch with a decorator tool. Wouldn't it be great if you could shift left and right with the deco tool? That would be awesome.