A single diabolical texture file, which made certain characters (like female nord vampires) have brown eyes instead of vampiric eyes.

Technically there is a mod out there that already does this... but... it has the bizarre ability to cause mounted combat to go screwy, for reasons I cannot fathom.

This is literally just one texture.  The one that is called for, for female human vampires.  You can use the provided texture, or replace it with your own.  You weren't going to use the stupid brown eye texture anyway.  The eye texture included is from The Eyes of Beauty: http://www.nexusmods.com/skyrim/mods/13722/? "eyeNenuphar" is the original name.  Feel free to rename any eyetexture you like to this one.  Hell, you don't even have to download this.  Just rename an eye texture you like to "eyehazelbrown".  You're welcome <3