To help with the inverted hp idea, Phanx suggestion would work like this.
Code:
self.Health.colorClass = true -- let oUF color the health bar
...
-- oUF Health will set the color of .bg if it exist
-- Using multiplier for shade of the Health bar
-- 1 is the default original color of the Health bar
self.Health.bg.multiplier = 1
-- Use PostUpdate to change the Health bar to your color of choice
self.Health.PostUpdate = HealthPostUpdate
Code:
local function HealthPostUpdate(health, unit, min, max)
health:SetStatusBarColor(r, g, b)
end