EDIT:
01 | local InRound = game.ReplicatedStorage.InRound |
02 | local Timer = game.ReplicatedStorage.Timer |
03 | local IntermissionScreen = game.StarterGui.Intermission.Frame |
04 | local Maps = game.StarterGui.Intermission.Frame.MapBox.Maps |
05 | local Menu = game.StarterGui.Menu.Frame |
06 |
07 | InRound.Value = false |
08 | Timer.Value = 20 -- intermission time |
09 | while InRound.Value = = false do |
10 | repeat |
11 | Maps.Visible = false |
12 | wait( 1 ) |
13 | Timer.Value - = 1 |
14 | until Timer.Value = = 30 |
15 | Maps.Visible = true |
And yes I'm pretty positive it's not a spelling error or anything like that
On line 8 you set the timer value to 20. So in the first repeat until loop, when you subtract one from the timer, it will never reach 30, as it is already below 30 and going down further.