Common Problem: Works in studio but not in real game?

HopperBin script works in studio but won't work in real game. Used to pick up items by clicking on them, and dropping them by clicking again.

holdRadius = 7
maxSelectRadius = 10

local position = Instance.new("BodyPosition") 
position.Name = "Pos"
position.maxForce = Vector3.new(100000,100000,100000)

local object = nil 

function onButton1Down(mouse)
    if mouse.Target ~= nil then 
        if (mouse.Target.Position - game.Players.LocalPlayer.Character.Head.Position).magnitude <= maxSelectRadius and not mouse.Target.Anchored then 
            position.Parent = object
            position.position = game.Players.LocalPlayer.Character.Head.Position + (mouse.Hit.p - game.Players.LocalPlayer.Character.Head.Position).unit * holdRadius
    end
end

function onButton1Up(mouse)
    object = nil
    position.Parent = nil
    down = false
local force = Instance.new("BodyForce")
    force.force = Vector3.new(0,90,0)
    force.Parent = object
    wait(2)
    force:Destroy()
end

function onMove(mouse) 
    if down then
        position.position = game.Players.LocalPlayer.Character.Head.Position + (mouse.Hit.p - game.Players.LocalPlayer.Character.Head.Position).unit * holdRadius
    end
end

function onSelected(mouse)
    mouse.Button1Down:connect(function() onButton1Down(mouse) end)
    mouse.Button1Up:connect(function() onButton1Up(mouse) end)
    mouse.Move:connect(function() onMove(mouse) end)
end

script.Parent.Selected:connect(onSelected)
script.Parent.Deselected:connect(onButton1Up)

help?