If all you want to do is change region/settlement names, you only have to edit 1 file, "imperial_campaign_regions_and_settlement_names"

This is the file that has the names set up like this:

{Inverness_Province}Inverness Region
{Inverness}Inverness

Do not change anything that is inside the brackets, only change what is outside. After you have made you changes, save and close the file.
*IMPORTANT* you must delete the BIN file that has the same name as the file that you updated (it is in the same folder). Then delete the map.rwm file from the base folder. When your new game loads, it will create new versions of these files, based on your new information. If you forget to trash these files the first time after making the update, you will crash.

I hope that helps.