without reading it all in deatil what you have written :-)) I think we all have this problem. One trick is not to do it in the terrain editor. Do a grayscale image in your favourite image processing software (Photoshop). I am very happy with 1200x1200 pixel (72 dpi). White is maximum height, black is minimum height. Paint the heights there or use other programs helping you doing that (CausticsGenerator for example - look for the correct name and URL in my last image). Then go back to the terrain editor. Reset everything and then go to "use image" (sorry i don't know the correct name - i am using a german version). Load your image and you will get a "perfect" terrain. Exactly what you wanted (if you define what you want after getting something). hope that helps a little

One day your ship comes in - but you're at the airport.