Textures, Sprites and all that jazz

First I will apology to the forum and its staff if this thread already exists in some form or another, but I tried to search for it and came up with nothing that was relevant. I am new to mods and I am just trying to figure a few probably basic things out without going for a full overhaul of units.

I would like to know if any of my fellow members noticed in a fresh installation of Rome, without any mods, that the textures on some units were almost incomplete. ex: the Julii faction and its early units(hastati and principes) are missing chainmail armour over their shoulders while it does exist in the .tga files. I was unsure why the sprite did not display the image of the armour and was wondering if anyone could explain.

As I aforementioned I am so green I make Eden look like a desolate wasteland. Thank you to anyone who responds.