Setting the restriction to 1 fixed the building immediately. That's one function I haven't played around with much. I though the numbers represented pixels, so it's good to know it's really tiles. I must have missed that part in the manual.
Thanks for explaining how the backend stuff works. It really helps when editing. I've read through the manual and managed the basics with some trial and error. I would love to say I completely understand, but I'm not there yet. I wish I had a better grasp on the more advanced tools, like Merge, Delete, and Create in tile mode.