This is one of the few times that I just went ahead and played an episode of OOB without picking at it first. (Frankly, I would need a Rosetta Stone in this case.)
So I am diving in and taking notes as I go, merely as a player.
First observations: Pretty map, nice choice of battle and foes. No Nazis, Tommies, or G.I. Joes for a change. Well-spoken briefing! The enemy is "deluded"? Very good.
First criticism: In the briefing, I can see where Jiujiang is located. I can surmise that the Lushan mountains is the range to the south, but why not label them as such?
It's the third briefing that goes astray in my opinion. It mentions "De'an and the railway towards Nanchang" but the player has no idea where that is because the camera focus stays north.
I suggest focusing on De'an with the third briefing and moving the second blurb in that briefing to the fourth briefing, as follows:

- Screenshot 2.jpg (529.11 KiB) Viewed 1007 times

- Screenshot 3.jpg (481.24 KiB) Viewed 1007 times
Notice, by the way, that I have corrected "the" to "they" at one point. Also, I believe that when one refers to direction, one does not capitalize "east," "west," and "southern." Only where a cardinal point is being referred to as a place, or ideology, etc., would it be capitalized, such as the headline "The West and East clash in World War III."
Also notice that I have temporarily moved the Chinese Heavy Infantry unit out of De'an so that the name will show. You could do this and move the unit back with a trigger on Turn 1 if you want.
It so happens that this unit, a "Chinese Collaborator" (how this will unfold is to be seen), has no AI team assigned to it? Intentional? I'm not sure if this unit will even defend itself without instructions. Perhaps you assign it to an AI team by trigger; I will take a look.
To be continued ...