I'm trying to make a custom planet that is very difficult to make but don't understand what controls that option in the tradewars editor. can anyone help? i also want this planet to be it's own class, as in, it has its own letter of the alphabet. how do I do that? all I see is how to base the planet on another planet and it winds up having a series of letters like cjhei or something. I don't want that, I want just the letter I, or J or whatever. thanks for the help.

Sorry to say , your limited to what TWGS is capable of .. and that is what you have run into.
Deal with the set that is given in TWGS , you still can make the planets whatever you want within the limits of the program.

Also take a look at other edits , you may find something you like.

Ok,
It's been a while since I played with gold planets, so if my memory is wrong, Harley or someone will correct me.
I'll just run through the whole thing.
First off, you have to have TW Gold.
Then when you do your big-bang, you have to have gold edits enabled. Option J?
Then after big-bang, highlight your game and go to the editor. Or telnet to your admin port.
Once in the editor, select option 2, edit planets or something, from the Gold Editors menu.
This gets you to the planet editor, where you can create or modify planets.
The Class of the planet (those letters) is based off of option B in the planet editor screen.
As you play with the options, you will get different classes and subclasses.
play around till you get the combination you want, or can at least live with. There are some letter combinations you can't get, but you can play around with it.
If you only want one letter, then you can only change one of the planet characteristics. (i.e. only have one that's not default or normal) When you have 2 that aren't default, you start getting those subclasses. I can't remember if the hability and hazzard settings get changed when you change the class. I think they are seperate.

Hope that helps.

To make it harder to make, add it as a class in addition to the default ones.

how do I add it as a class in addition to the classes there? There is no option for that.