There are certain dds files that won't be open or even converted off websites,
for example this DDS file in global.iff cannot be opened: headband_color.ff29da8b1db64346.dds
while this one can: iris_color_brown.13fbc4505c14a413.dds
and hair textures cannot be opened as well, so I don't know how to change the color of any hair.