Ok, got a chance to play around with this a little.
I started out trying to change France's DCN so their name would flow this way:
Frankish Empire > West Francia (844 AD) > Kingdom of France (987 AD).
I discovered that the latter two names had entries under the Text XML file, but didn't have corresponding ones in the CIV4CivilizationInfo.xml file. I tried setting it up this way(all these lines are near the bottom of the DCN Conditions before it ends and goes to actual Civ unit/Leaderhead info):
Basically what i did was make it so the names would change after a certain turn (86 for West Francia, 129 for Kingdom of France). I also tried rearranging the tag order so it would flow logically (FRA01 is Kingdom of France, FRA02 is West Francia, Etc...)
However, loading back into a game the name still shows after turn 86 as Frankish Empire.
Is there something else i need to change for the names to work? I tried looking at Arabia and Bulgaria for examples because their name changes work, and for Arabia going to Fatimid, Ayyubid, and Mamluk seems tied to Province #103, while Bulgarian Empire and Second Bulgarian Empire appears tied to Type/Number of Provinces (2).
Any Suggestions?
EDIT: Nevermind, i loaded a new game as Burgundy and going to turn 87 made West Francia appear. It looks like you need to start a fresh new game for the change to take effect. i'll need to experiment to see if it is consistent though.
EDIT2: after turn 129 name is stuck at West Francia. I'm wondering if tag FRA01 needs to be changed to something else?