Heh, yeah, I noticed that double/triple posting too.
If I remember that old discussion.... There are two main tools you'll probably need. A disassembler, and a hex editor. You can google for both things, and you should find some free downloads. I usually use OllyDbg for a disassembler, and XVI32 for a hex editor. Both were free downloads that I found with google.
Open the .dll file for the level, and search the imports for SetColor. (In OllyDbg, hit Ctrl+N from the main code window). The name will be decorated, so it will have lots of odd junk and symbols around it. Don't worry about it. Follow it in the code. Careful though, since it may be called a few times, and you'll want to find the right one. It will likely be called twice in a colony game, setting the color for each colony. Look in the code where it has CALL and then the decorated name. Look up a few lines. This part is a little different for each case. It might be the line directly above, or it might be a few lines above it. You should see something along the lines of PUSH 0 (or 1, 2, ..., 5). This is the player color being set. This is how you'll know if you've found the call for setting the right colony's color. That's the line you want to change. Change the number to the new value (0-5 is definately safe, maybe some odd effects beyond that).
What are the colors anyways? 0 = Blue? 1 = Red? 2 = ...?
If you want to write the changes permanently to a file with a hex editor, here's an easy way to do it. Take a look at the original code bytes and search for them. (To the left of the assembly instruction). When searching for those bytes *make sure they are unique!* You don't want to edit some random place in the file that may have been similar. You may have to add bytes for a few lines to make sure it's unique. When you edit the instruction, OllyDbg shows the new code bytes, overwrite the location you found in the hex editor with the new code bytes. There should only actually be one byte different, corresponding to the color value. Save the file and test it out.
Note: If you changed the instruction already and want to see the old code bytes, you can undo changes/patches in OllyDbg by highlighting that line and pressing Alt+BkSpc.
Another way to edit colors, is to change the actual palette of player colors. This affects the whole game globally. The changes aren't confined to just one level. You can also add truely new colors this way. Keep in mind that player colors aren't solid. They contain a slight gradient of colors. When editing them, you have to edit the whole range of Blues/Reds/whatever used by that player color value. You can do this with a hex editor alone, although it's easier with some sort of bitmap/palette editing tools.