Well, I figured it out! After I create and find a terrain I like at 256 grid size, I uncheck the random extent, random position and random character. Then I increase the grid size to what I want, click new and then the fractal button and I get a new terrain like the last one, except at a higher res!
BTW, I couldn't find anywhere in the book where it talked about these options, or the tile options. Where can I find info on these?

[Tim]