EDIT:
local InRound = game.ReplicatedStorage.InRound
local Timer = game.ReplicatedStorage.Timer
local IntermissionScreen = game.StarterGui.Intermission.Frame
local Maps = game.StarterGui.Intermission.Frame.MapBox.Maps
local Menu = game.StarterGui.Menu.Frame
InRound.Value = false
Timer.Value = 20 -- intermission time
while InRound.Value == false do
repeat
Maps.Visible = false
wait(1)
Timer.Value -= 1
until Timer.Value == 30
Maps.Visible = true
repeat
wait(1)
Timer.Value -= 1
until Timer.Value == 0
IntermissionScreen.Visible = false -- this line and below are the one's not working
Menu.Visible = false
InRound.Value = true
-- script the code that will teleport only the players on the intermission screen
end
And yes I'm pretty positive it's not a spelling error or anything like that

3 comments
DId you add in a repeat statement in the first line?
Is that your whole script?
Yes there's a repeat statement above, and no that's not my whole script. I'll edit it into the post