Okay, so I fubared again. I spent 3 hours making an immaculate park with only maxis terrains, a few floors and at the most 10 types of plants in various colors I've tried and tested before and huge swimming pools. Oh and 2 dozen lamps and some maxis fences. I made it on a large lot (but not the largest- 5x3 I suppose). Saved and exited to neighborhood. Now there's a big black lot right in the middle of my neighborhood, and I can't click on it even to bulldoze it.
So I moved the neighborhood to my test game with no downloads, and the lot is still there, still black. When I change my viewing angle, it turns bright view, like a mirror held to the sky. (I remember that color from when I put in a lot with a hill on the back-side on a flat neighborhood, and the terrain ripped to show me what was underneath. But it was maybe 5 neighborhoods ago) Anyway, I tried changing the terrain with the terrain surgery tutorial, accomplished with no problems (I'm an expert on this now) and the big gaping black hole is still there. So I looked at the lot in Simpe, didn't see much difference compared to the other lots, and removed it from my game manually afterwards. Now I check the neighborhood looks just fine- no gaping hole!
Why did this happen? What can I do to prevent this from happening again? Is there any way I can save this lot?
I'll try anything to save it, or stop it from happening again. I don't want 3 hours of my life gone towards nothing (I mean, I do waste lots of time playing the sims, but I have fun dammit!)
edit:(changed title)