Here is the problem I made a scene with a population of trees, first I made a quick test and I adjust "Area lenght a" and "Area length b" to 20000 each a quick render and all is fine but to cover the region of the scene I have to increase "Area lenght a" and "Area lenght b" to 40000 each I made a full render (800X600) anti-Aliasing at .6 and Detail at 5, I start the full render and maybe after 5 minutes of rendering Terragen 2 shut down, my computer specs are AMD Athlon 3500, Windows XP home, 3000Mb Virtual memory and I just (yesterday) upgraded my RAM from 1GB to 2GB. Does anybody have the same problem? Thanks.