The more I use Nature Terrain Generator, the more I realize that it's an incredible, wonderful tool that was not quite ready for release.  I'll put aside for the the issue that when morphing tiles it is ridiculously easy for the tiled surface to suffer terrible tears where they should have remained connected.  It's annoying having to scan every seam from every angle just to make sure there are no tears, and then do it again after fixing the tears to make sure the fix did not open a new tear.
Anyhow, my real issue involves generating large terrains.  I need a 20x20 surface, which is just 80 meters on a side, not excessively large for an area for character exploration.  My generation ran for four hours before I gave up and killed it.  I do wish there were a progress bar!  So I figured I'd just do four 10x10 surfaces and stitch them together.  I was happy when my first 10x10 took just 8 minutes to generate.  I slid it 4000 units left to get it out of the way and then tried to generate a second 10x10.  An hour later it was still humming away, and when I clicked on the screen to see if it was still alive (Windows called it unresponsive), iClone just vanished, a total crash.

So, is there an upper limit?  Is it illegal to generate a second terrain when there is already one in the project?  Is this just yet another NTG bug?  Do you suppose the developer has any plans for fixing this highly promising program?  This is so frustrating!