Re: Sim must have a height gap error?
If you put the platforms down first then put walls on top of them, then that is probably why you can't pull the foundation up. There isn't one when you do it that way. Platforms are meant to go on top of a foundation, not flat on the ground, so the best way to go about it is to build your walls first using the room or wall tool and then pull the foundation up before doing anything else. Then put in any platforms.
So to fix your build you may have to tear down the walls on the ground level, delete the platforms, and then draw the walls again. Once you have your rooms defined, pull up the foundation a couple of clicks (you can adjust the height later on). Then you can put the platforms in on top of the foundation. I would also put in the basement before adding the platforms as well, if you are going to use any recessed platforms.
Hope this helps
