About
World Builder was created using Borland Delphi, and is free software. I have not yet made the source code available, but will probably do so at some point in the future. If you are interested in getting a copy of the source code, please feel free to email and ask me for it -- in its current state it should be compilable on other systems (though it uses a couple of freely available third-party components), but the compilation process is not completely straight-forward.
World Builder is a front-end to a command-line program (also included) called planet.exe, developed by Torben Mogensen.
For more information about 'planet' see the About Planet pages in this Help file, or see Torben Mogenson's own home-page.