Why doesn't this LocalScript work? [Still unanswered]

I have tried everything to make this GUI function, but it never does. What exactly is the problem, really? Seems impossible to fix. (LocalScript updated, which still won't work)

local bootup = game.Players.LocalPlayer.PlayerGui.CyborgVision.PowerAndHealth.EmergencyReboot.BootUpLabel.Visible
local shutdown = game.Players.LocalPlayer.PlayerGui.CyborgVision.PowerAndHealth.EmergencyReboot.ShutDownLabel.Visible
local frame = game.Players.LocalPlayer.PlayerGui.CyborgVision.PowerAndHealth.EmergencyReboot.Visible

if game.Players.LocalPlayer.Character.Humanoid.Health <= 10 then
    mouse = game.Players.LocalPlayer:GetMouse()
    mouse.KeyDown:connect(function(key)
        if key:lower() == "z" then
        frame = 1
        game.Players.LocalPlayer.Character.Humanoid.AutoRotate = false
        game.Players.LocalPlayer.Character.Humanoid.WalkSpeed = 0
        wait(2.5)
        shutdown = 0
        wait(4)
        bootup = 1
        wait(1.5)
        frame = 0
        shutdown = 1
        bootup = 0
        game.Players.LocalPlayer.Character.Humanoid.AutoRotate = true
        game.Players.LocalPlayer.Character.Humanoid.WalkSpeed = 16
        game.Players.LocalPlayer.Character.Humanoid.Health = 100
    end
    end)
    end