It happened to me twice yet.

I created some simple mountains some days ago, saved Builded, played it and all that.

And randomly at any day that part of the world is flat....

Tomorrow i got the mountain and played it (thou c++), and today the mountain has desapeared

Hi,
I didn't experience anything like that, if you'll find how to reproduce this issue, please let me know.

I know

The strange thing is that I didn't did anything, I mean yesterday at night I worked on that world and today at morning the mountain has gone =D

Probably I'm doing something wrong like always