Script doesn't work

[the flyers]

Hi every one !
I have recently downloaded eSpeedometer from garrysmod.org but that doesn't work and the creator doesn't reply to my request !
The numbers stays at 0.00, do you know what's wrong in that script ?
[lua] /*
2D Speedometer
Version 1.0 Public
© Night-Eagle 2008
gmail sedhdi
*/

surface.CreateFont( "lcd", 36, 2, 0, 0, "lcd36" )

hook.Add("HUDPaint","espeedometer.paint",function()
local conv = 17.6
local max = 114

local speed = LocalPlayer()
if LocalPlayer():IsValid() and LocalPlayer():InVehicle() then
speed = speed:GetVelocity():Length()/conv
else
return
end
//speed = CurTime()*50%(max+30)

draw.NoTexture()
surface.SetDrawColor(0,0,0,128)

local a = Vector(ScrW()*.5,ScrH(),0)
local s = math.ceil(ScrW()/12/8)*8
s = s

surface.DrawPoly{
{
x = a.x - s*.5,
y = a.y - s*.125,
},
{
x = a.x + s*.2,
y = a.y - s *.3,
},
{
x = a.x + s*.5,
y = a.y - s *.3,
},
{
x = a.x + s*.5,
y = a.y,
},
{
x = a.x - s*.5,
y = a.y,
},
}

local alpha = 32
for i = 0,math.min((speed/max)*(s/6-1),s/6-1) do
if i < s/48 then
surface.SetDrawColor(0,0,255,alpha)
elseif i < s / 10 then
surface.SetDrawColor(0,255,0,alpha)
elseif i < s / 7 then
surface.SetDrawColor(255,255,0,alpha)
else
surface.SetDrawColor(255,0,0,alpha)
end

//surface.DrawRect(a.x-s*.5+6*i+1,a.y-s,4,s)
/*
.3-.125
.175
s*.7
*/

local x = s*.5+6*i
local c = 1-s
local v = s/128
local b = -s/32
if i < s/8.5-1 then
surface.DrawPoly{
{
x = a.x + c+x,
y = a.y - x*.25+v,
},
{
x = a.x + c+x+4,
y = a.y - (x+4)*.25+v,
},
{
x = a.x + c+x+4,
y = a.y+b,
},
{
x = a.x + c+x,
y = a.y+b,
},
}
else
surface.DrawPoly{
{
x = a.x + c+x,
y = a.y - s*.3+v,
},
{
x = a.x + c+x+4,
y = a.y - s*.3+v,
},
{
x = a.x + c+x+4,
y = a.y+b,
},
{
x = a.x + c+x,
y = a.y+b,
},
}
end
end

local speedstr = tostring(math.Round(speed*10)/10)
if string.sub(speedstr,-2,-2) ~= "." then
speedstr = speedstr .. ".0"
end
draw.DrawText(speedstr,"lcd36",a.x+s*.5-8,a.y-36,Color(255,255,255,200),2)
end)
[/lua]
Thanks a lot !
Ps : sorry for my bad english, i'm french !