I have the same problem. I have tried everything suggested here, and then some, and nothing has worked. When I uploaded it to my library and placed it in a different world, I still had the same problem. I couldn't bulldoze it so I quit without saving so I would not have 2 borked lots to contend with. This must be a new bug introduced with one of the recent updates we had, because I have never run into this problem before. I hope someone figures out how to fix this because I was just about finished with my latest lot when this happened. I would really hate to lose the chance to upload this lot as I have play tested it and I had a lot of fun with it. It is a Nuclear Research Facility for scientists to hone their skills.
