2D Grid Placement System

[EnoughPlenty]

Greetings. I am trying to make a grid placement system for my level editor, but the frames arent staying on the correct positions. This is the code:

local CAMX,CAMY = 0,-1.5

local background = script.Parent:FindFirstChild("Background")
local floor = script.Parent:FindFirstChild("Floor")
local UIS = game:GetService("UserInputService")
local LevelFolder = script.Parent:FindFirstChild("LevelFolder")
local ItemsFolder = script:FindFirstChild("Items")
local Mouse = game.Players.LocalPlayer:GetMouse()
local Brush = nil
local gridsize = 0.04
local width,height = 32,23
local ghostblock = nil

local function GetSnappedPosOfMouse()
	local posx,posy
	
	posx = math.floor(((Mouse.X + CAMX)/32))
	posy = math.floor(((Mouse.Y + CAMY)/32))
	
	return Vector2.new(posx,posy)
end


local function UpdateGhostBlock()
	if Brush == nil then if ghostblock then ghostblock:Destroy() ghostblock = nil end return nil end
	if ghostblock == nil then
		ghostblock = ItemsFolder:FindFirstChild(Brush):Clone()
		ghostblock.Transparency = 0.3
		ghostblock.Parent = script.Parent
	end
	local SnappedPos = GetSnappedPosOfMouse()
	ghostblock.Position = UDim2.new(0,SnappedPos.X,0,SnappedPos.Y)
end

local function StepCamera()
	background.Position = UDim2.new(0,0,-10.1-CAMY,0)
	floor.Position = UDim2.new(0,0,-0.8-CAMY,0)
end

UIS.InputBegan:Connect(function(key, isTyping)
	if not isTyping then
		if key.KeyCode == Enum.KeyCode.One then
			Brush = "Block"
		elseif key.KeyCode == Enum.KeyCode.Zero then
			Brush = nil
		end
	end
end)


local OldMouse = UIS:GetMouseDelta()
Mouse.Button1Down:Connect(function() M1Down = true end)
Mouse.Button1Up:Connect(function() M1Down = false end)
Mouse.Button2Down:Connect(function() M2Down = true end)
Mouse.Button2Up:Connect(function() M2Down = false end)

UIS.InputChanged:Connect(function(key)
	if key.UserInputType == Enum.UserInputType.MouseMovement then
		if M2Down then
			local MouseDelta = UIS:GetMouseDelta()
			local result = Vector2.new(MouseDelta.X - OldMouse.X, MouseDelta.Y - OldMouse.Y)
			CAMX -= MouseDelta.X/100
			CAMY -= MouseDelta.Y/100
		end
	end
end)

game:GetService("RunService").RenderStepped:Connect(UpdateGhostBlock)
game:GetService("RunService").RenderStepped:Connect(StepCamera)

Thanks in advance!