Great mod and idea!! In "read me" you said that if there is any typos or historical inaccurasies you want them to be corrected.
Well here is few minor typos (cities):
-"Philipopolis" --> Philippopolis
-"Sirminum" --> Sirmium
-"Vindobonna" --> Vindobona
-"Augusta Trevorum" --> Augusta Treverorum
-"Cartago" --> Carthago
-"Antiocha" --> Antioch
-"Nisbis" --> Nisibis
-"Sarminsegatuza" --> Sarmizegethusa (wrong place btw, you can see correct place from
here. Its in finnish but you can see the city place)
-"Porolisium" --> Porolissum
I noticed also that Germania Superior is controlled by Germanic tribes and its in wrong position. You can see the correct place from here:
http://en.wikipedia.org/wiki/File:Roman_Empire_125.svg
Also the area between Upper Rhine and Upper Danube (
Agri Decumates) should be under Roman control. It was conquered by Flavian Emperors (Vespasian I think). You can see the area in map above and
here.
EDIT: The description for the main campaign is little inaccurate. Nerva was not murdered by Casperius Aelianus. He died of natural causes.
Good luck! +rep