This is just a very simple script. Put it in your main sauerbraten folder, then add this line to your autoexec:
exec coloredmaptitle.cfg
and save. When you start up Sauerbraten the next time you should get a message about the color GUI being successfully installed.
With F8 you can call up a small window. With that you can make colored maptitles. It is somewhat easy to use, at least way easier than all those control-shift or control-alt combinations or however that worked...
In case you are really totally lost, there is a long description in the window self.
In addition does it include some new variables. These are mostly for command-line usage. Those codes like ^f3 (which are used to color strings) don't work when you type them directly ingame. The variables I mentioned are containing exactly those codes, what makes it possible to use them directly ingame. How to access (also pretty easy) is written in the description too.