So I was working on a skyscraper in Creative mode. I used the 'tunneler's dream' preset, because one of my other creations required at least 100 blocks of stone deep.I was only able to place blocks of iron up about 25 to 26 blocks above ground level. it won't let me place any blocks after that. I tried using Overworld preset, and got an extra 10 blocks up. The only one that works for high buildings is Classic Flat, 3 dirt on top of bedrock. But this doesn't work for my tunnel-requiring builds. I may have to create a new world using Classic Flat for my Skyscraper city and just get used to changing worlds a lot. But I would prefer for all my builds to be in one world, for the sake of expediency.
And please don't ask me to join any servers, i'm having trouble with logging in to my account...
ahhhh.... right, i forgot. Chunks stop at y=256 so I can't build that high. I think I might use like Overworld or something, about 50 deep or so. But if I need something really tall, i'll need a Classic Flat map. That was stupid of me.