I would like to ask a few questions about creating new landscapes.

1. How to create a landscape of a limited size? I have put in limits when I created new ones, but they do not seem to affect it. Whenever I load a new wilderness cell, many more are spawned around it.
2. Is there any specific danger in working with new landscapes that could break them? I have heard about the hightmap editor crashing all the time and that some "generation" of something related to cells takes many hours per cell.

*BUMP*
As I really would like to find answers to this.

Don't worry about other Wilderness cells loading, just create the landscape you want and let it fill as many cells as it needs. Also, the heightmap editor is broken.