How to change color settings of a texture
 

Possible to change the colors of a texture in ESO? mess with hue values or anything? I want to change the colors of the group indicators above peeps heads

If you are working with texture control, it is pretty easy, just use SetColor method.

However group indicators aren't UI controls and you can't access them from UI (there is just switch to enable/disable them).
All you can do is adding new floating markers for map pin type - the same way as you do in your PapaCrown for group leader. And as far as I know, whole map pin type group must have the same floating marker, so you can forget different marker colors for each party members.

Thanks Garkin :) Pro as always