Plane GUI problom?

The GUI in the plane that I use not working any more I think its problem with the Mouse Icon GUI its a GUI that is suppose to replace the Mouse Icon,and It is linked with the controls and they dont work eather,so If anyknows how to fix this problem please contact me on my roblox account its bosetroller.The tools works in studio test mode but not in online mode,anything wrong with this script?

local object = Instance.new("ObjectValue") object.Value = script.Parent.Parent.Parent

seat = script.Parent.Seat

function onSitUp(child, hopper, plane)

if child.Parent == nil then
	PS = hopper.Parent.Parent.PlayerGui:findFirstChild("PlaneStats")
	if PS ~= nil then PS:remove() end
	hopper.Parent = nil
end

end

function onChildAdded(part) if part.className == "Weld" then

	local HumanoidRootPart = part.Part1
	if HumanoidRootPart ~= nil then

		local char = HumanoidRootPart.Parent
		local player = game.Players:GetPlayerFromCharacter(char)
		if player ~= nil then
			local regen = script.Parent.Regen
			regen.Anchored = false
			local hopper = game.Lighting.FA18E:clone()
			hopper.Parent = player.Backpack
			hopper.Name = "F/A-18E Super Hornet"
			part.AncestryChanged:connect(function(child) onSitUp(child, hopper, script.Parent.Parent) end) 
		end

		local parent = HumanoidRootPart.Parent
		if parent ~= nil then
			script.Parent.Parent.Parent = parent
			while true do
				wait(2)
				if part == nil then
					script.Parent.Parent.Parent = game.Workspace
					script.Parent.Parent:MakeJoints()
				break end
			end
		end
	end
end

end seat.ChildAdded:connect(onChildAdded)