I’m not exactly sure what I’ve done to cause this, but my landscape is now missing parts that used to be present, and for some reason I can’t add it back using Manage>Add. I’m thinking of deleting all layers and starting over just out of sheer frustration at this point.
I too am extremely frustrated. My landscape is fine while I am creating and editing, but after hours of work and I save and close - Next time I open, the WHOLE landscape is gone!