Colors for the bars are set by group (by default there are three groups: buffs, debuffs & tench)
By default debuffs are colored in the color coresponding to their type (blue for magic, green for poison, ...). These colors are the default Blizzard colors and there is no way in EBB to change them.
But you can create a new group, set it up to show only the debuffs you want, asign it a different color and disable coloring by debuff type for that group.
happens to me today as well, tinytip is one of the few addons i happened to update just today, and after that update, i get a blank index and reload index did not help at all...awaiting for solutions...