Shoutbox

OK, it's easy:

Start -> Run -> "regedit" -> OK

As mentioned earlier, navigate through HKEY_CURRENT_USER\Software\Patchou\Messenger Plus! Live\your@email.com\Preferences

See if the right-hand panel has a value name "AutoMsgTextColor", if not, right-click on it and click "New -> DWORD value"
After filling AutoMsgTextColor in the value name, double click it and input a color.

Well, the color is a RRGGBB format, each component (for example, RR) ranges from 00 to ff; to make things simple, if you don't know what value to fill in, how about telling us the color you want and we tell you the color code?