several tips about cultures in Central-Eastern Europe:
(1)"Livonian" shold be named ruther "Lettish" and it is better to split Latgalian from it (but not necessary).
(2)Smolensk and Severia for the 15th-18th centuries are defiantly Ruthenian not Russian (still there are not much differences).
(3)Warmia should be German (Ostseer):
http://img20.imageshack.us/img20/3645/prusy.png
Pomerelia should be "Kashubian"
1. Latgale (latgalian) or Latvia could be better, agree.
2. Wrong. Smolensk is and was rus. city from the moment of foundation. Anyway, could anyone prove existing of "ruthenians", because word "ruthenian" means "russian" on latin language. So it is the same.
3. German Ermland (Ermenland) or prussish Elbing, agree.
What is Severia? Novgorod-Severskij? Though there could be Chernigov. What is the region, named "Ukraina"? Mate, use Poltava! It's obviously. Poltava is ancient city (known from 12 cent., but founded even earlier). It is 100% match to the game. I also surprised, why there is no Kiev – one of the most ancient european cities and known as "Mother of russian cities"? Zhitomir is also ancient (founded in 884th, but known from 1392th), but not so significant as Kiev. You could rename Luck (don't even know what is "Luck") into Zhitomir. Braclav is acceptable (f. in 1362th), but Vinnitsa (f. in 1355th) is main centre of this region (Podolje). Taurida, K(o)uban' and Stavropol' – good find. Kuban would be more correct, it is also the river's name. You could make your own transcription with using verbalization programm
http://text-to-speech.imtranslator.net/
"Navanradak" is Novogrudok, founded in 1044th by rus. Grand duke Yaroslav the Wise. (j)Edisan (Jedisan is german variant) was named so just in 18th century after Edisan nogai Horde migration from Kuban'.
And about Central Asia. You placed uzbeks in Turkmenia. GregoryTheBruce (post #52) did great point with providing ethnic map of the region. Though it is modern map, but also acceptable, because in-game regions not so precise.
Khazars – don't know, but they were fighting with Kiev, how could they did this, if they were in Central Asia?
Also I have idea to rename finnish lands in finnish manner (by finnish tribes names) instead swedish names. If you interested, let me know.
And please answer – what are the 2 provinces: one to south from Luck, another one is to south from Zhitomir. These provinces has common border on the map from first page.