Inventory system not working and very glitchy. Help?

numbers = {}
local add = require(workspace:WaitForChild("SourceScript"))

--[[is a modulescript in workspace. only instance i add is an ImageButton and args are add.instance(name, instance, parent)
]]


local function Update()
	for i,v in pairs(numbers) do
		table.remove(numbers, i)
	end
	for i,v in pairs(script.Parent:GetChildren()) do
		if v:isA("ImageButton") then
			v:remove()
		end
	end
	local Spot = 1
	for i,v in pairs(game.Players.LocalPlayer:WaitForChild("Inv"):GetChildren()) do
		table.insert(numbers, v)
		table.sort(numbers, function(x,y) return x.Spot.Value < y.Spot.Value end)
		if numbers[i + 1] then
			if v.Spot.Value < (numbers[i + 1].Spot.Value - 1) then
				numbers[i + 1].Spot.Value = v.Spot.Value + 1
			end
			if v.Spot.Value >= 4 and v.Spot.Value < 7 then
				v.rowNum.Value = 2
			elseif v.Spot.Value >= 7 and v.Spot.Value < 10 then
				v.rowNum.Value = 3
			elseif v.Spot.Value >= 10 and v.Spot.Value < 13 then
				v.rowNum.Value = 4
			elseif v.Spot.Value >= 13 and v.Spot.Value < 16 then
				v.rowNum.Value = 5
			elseif v.Spot.Value >= 16 and v.Spot.Value < 19 then
				v.rowNum.Value = 6
			end
		end
		local newButton = add.instance(i, "ImageButton", script.Parent)
		newButton.Name = v.Spot.Value
		newButton.Size = UDim2.new(.25,0,.1,0)
		newButton.Image = game.ReplicatedStorage[v.Name].Texture
		script.delScript:Clone().Parent = newButton
		newButton.delScript.Disabled = false
		Spot = Spot + 1
		if v.Spot.Value == 1 or v.Spot.Value == 4 or v.Spot.Value == 7 or v.Spot.Value == 10 or v.Spot.Value == 13 or v.Spot.Value == 16 or v.Spot.Value == 19 then
			newButton.Position = UDim2.new(.065 ,0,(.125 + ((v.rowNum.Value-1)*.25)/2),0)
			Spot = 1
		else
			newButton.Position = UDim2.new((.065 + (.3 * (Spot-1))) ,0, (.125 + ((v.rowNum.Value - 1)*.25)/2), 0)
		end
	end
end

Update()
Update()
script.Parent:WaitForChild("money").Text = "Money: $"..game.Players.LocalPlayer:WaitForChild("stats"):WaitForChild("money").Value

game.Players.LocalPlayer:WaitForChild("Inv").ChildAdded:connect(function(child)
	child:WaitForChild("Spot")
	Update()
	Update()
end)

game.Players.LocalPlayer:WaitForChild("Inv").ChildRemoved:connect(function(child)
	Update()
	Update()
end)

game.Players.LocalPlayer:WaitForChild("stats"):WaitForChild("money").Changed:connect(function(value)
	script.Parent.Money.Text = "Money: $"..value
	script.Parent.Parent.CoinSound:Play()
end)

When it updates, the gui glitches out and pretty much doesn't work. What have I done wrong?

Please tell output but anyway...

Does SourceScript return a table??? If not, that's your problem. You can't index functions in ModuleScripts using function() end .

Try changing the instance function in the table; by following this example: YourKeyNameHere.FunctionName = function(name, instance, parent)

Hope this helps! If not tell output. ~marcoantoniosantos3