If you've been itching to make your own dream planet and don't mind doing a little minor surgery on the game's data files, read on! It's not difficult, but it does require rudimentary knowledge of XML and basic file editing skills. For this example, I'll be changing the appearance of the Yor's home star system and planets, but the steps can be applied to any of the game's races (including the custom race). I won't cover every little detail, but by the time you've finished reading this article, you should have enough information to go forth and create your own custom planets.
Before you do anything else, you should make backup copies of the files you're going to be editing, namely, CustomPlanets.xml and RaceConfig.xml. You'll find these files in the Data\English directory of the game's install directory. It is possible to make the game unplayable if you mess up these files, so save yourself a tech support call by backing up these files! Also, make sure you're editing the normal game data files and not the Metaverse data files--changing the Metaverse data files in any way could very well make it so that you can't submit games to the Metaverse!
Now that you've backed up those files, open CustomPlanets.xml in notepad. I recommend using notepad because it won't try to add strange text formatting tags or other XML junk that can derail the game's XML parsing code. If your favorite editor doesn't add anything more than what you type, you can use that too.
In CustomPlanets.xml, find the StarSystem node whose Name attribute is "Icos". This node defines the data used to describe the Yor's star system. I edited mine to look like this:
<StarSystem Name="Custom Yor">
<DisplayName>Lapeer</DisplayName>
<Planet Name="Almont">
<DisplayName>Almont</DisplayName>
<Class>15</Class>
<RAWTerrain>Strange.raw</RAWTerrain>
<Rings>gfx/planets/R03.png</Rings>
</Planet>
<Planet Name="Lapeer II">
<DisplayName>Lapeer II</DisplayName>
<Class>0</Class>
</Planet>
<Planet Name="Lapeer III">
<DisplayName>Lapeer III</DisplayName>
<Class>0</Class>
</Planet>
<Planet Name="Lapeer IV">
<DisplayName>Lapeer IV</DisplayName>
<Class>4</Class>
</Planet>
</StarSystem>
Here's what I changed from the standard Yor star system:
1. In this example, I've taken away one of the (useless) class 0 planets that the Yor would normally start out with. Feel free to add or remove planets as you like, but to avoid undesired behavior, stars should always have between 1 and 5 planets (inclusive).
2. I've changed the Name attributes and DisplayName tags so that the Yor's star is named "Lapeer" and their home planet is named "Almont". The other planets in the system are named "Lapeer II", "Lapeer III" and "Lapeer IV".
3. I bumped up the initial quality of the Yor's home planet from 10 to 15 by changing the value of the Class tag. Planet classes can range from 0 to 26, but you should make sure the home planet is usable (i.e., is at least class 3).
4. Finally, I gave the home planet a custom surface by specifying the name of a raw bitmap file. More on that a little later.
Save your changes and open RaceConfig.xml. Find the Race tag with a Name attribute of "Yor Collective". Change the value of the Homestar tag from "Icos" to "Lapeer" and the value of the Homeworld tag from "Iconia" to "Almont". Save your changes. You're two thirds of the way there!
The final step in creating your own custom planets is to make a height map that describes the planet surface. For this purpose, GalCiv 2 uses 384x192 8-bit grayscale images saved out as raw (i.e., headerless) data. The simplest way to create a height map is to use an off-the-shelf paint program to "paint" a height map. I use Paint Shop Pro, the programmer's paint program, but Photoshop will probably do the trick too. Basically, the whiter a pixel is, the higher the elevation in the generated terrain. So, pure black pixels will appear as deep oceans and pure white pixels will appear as snow-covered mountain peaks. What happens in between depends on the planet's class, but those details would probably bore you and they're apparent enough when you see what happens in the game. Once you've created your height map, save it to the Data\HeightMaps directory of the GalCiv2 install directory. For our example, I named my height map file Strange.raw.
If you made these changes with the game running already, you'll need to exit the game and restart it for your changes to take effect. Start a new game playing as the Yor and enjoy your handiwork!