Looks like it. If that's the case, have you downloaded and installed the patch I've added to the first post in the VD thread?
Okay, another idea: go into Assets\XML\Civilizations\CIV4CivilizationInfos.xml and change Congo's ArtStyleType from ARTSTYLE_AFRICA to ARTSTYLE_AFRICAN (or maybe the other way around).
You're fighting barbarians, I assume? They don't give xp towards GGs.