Sample model

test82models.lua

function Test82Models()
    local Redraw = function(self)
        if not self.model_path then return end

        self:SetModelScale(1)
        self:SetPosition(0,0,0)

        self:SetModel(self.model_path)

        self:SetModelScale(self.model_scale)
        self:SetPosition(self.ox, self.oy, self.oz)
    end

    local ResetTransformations = function(self)
        self:SetModelScale(1)
        self:SetPosition(0,0,0)
    end

    local MakeModelRegion = function(parent, w, h, model_path, x,y,z)
        local pmf = CreateFrame("PlayerModel", nil, parent )
        pmf:SetSize(w,h)

        pmf.model_scale = 1
        pmf.ox = x
        pmf.oy = y
        pmf.oz = z
        pmf.model_path = model_path

        pmf:SetScript("OnHide", ResetTransformations)
        pmf:SetScript("OnShow", Redraw)
        pmf.Redraw = Redraw
        pmf.ResetTransformations = ResetTransformations
        pmf:Redraw()

        return pmf
    end

    local is82 = select(4,GetBuildInfo()) > 80100

    local ambientSmoke = MakeModelRegion(nil, 200, 200, is82 and 165535 or "spells/acidburn_blue.m2", 0,0,1 )
    ambientSmoke:SetPoint("CENTER", UIParent, "CENTER", 0, 0)
end