script.Parent.Text = (game.Players.LocalPlayer.Name.. "'s UserID is ".. game.Players.LocalPlayer.FollowUserId)
The text is supposed to say your name, and your Id, but it tells you your ID is 0 any help?
The property you're attempting to concatenate will always be 0 unless the user in question followed another user into the game, in which case the property will be equal to the userId of whoever they followed.
You should be 'reading' the userId property to get their userId.
http://wiki.roblox.com/index.php?title=UserId
local Player = game.Players.LocalPlayer script.Parent.Text = Player.Name .. "'s UserID is " .. Player.userId