RooFit paramOn change text

Hello, how is it possibile to manage the visual property of the box used by paramOn, for exaple:

import ROOT

x = ROOT.RooRealVar("x", "x", -5, 5)
mu = ROOT.RooRealVar("mu", "mu", 0, -1, 1)
sigma = ROOT.RooRealVar("sigma", "sigma", 1, 0.1, 2)
pdf = ROOT.RooGaussian("gaus", "gaus", x, mu, sigma)

data = pdf.generate(ROOT.RooArgSet(x), 10000)

pdf.fitTo(data)

frame = x.frame()
data.plotOn(frame)
pdf.plotOn(frame)

pdf.paramOn(frame,
            ROOT.RooFit.FillColor(ROOT.kRed),
            ROOT.RooFit.Label("Global Fit parameters:"),
            ROOT.RooFit.Layout(0.1, 0.4, 0.9),
            ROOT.RooFit.Format("NEU", ROOT.RooFit.AutoPrecision(1)),
            ROOT.RooFit.ShowConstants())

canvas = ROOT.TCanvas()
frame.Draw()

# I really don't like this
canvas.GetListOfPrimitives().FindObject("gaus_paramBox").SetTextColor(ROOT.kRed)
# this crash my computer:
canvas.GetListOfPrimitives().FindObject("gaus_paramBox").SetTextSize(14)

and why the label “Global fit parameters” is on the bottom?

+1 for label issue. The header label is rendered on the bottom of the parameter box. Apparently, it should be placed above the parameters list. Tested ROOT 6.06/02