Custom GUI Responsive when tested in studio, but not in an actual server?

Hey guys! First off, thanks for taking the time to view my question. As for my problem: I created a custom chat gui (just for the hell of it), and it's working great when I click "test" in the studio. The problem I'm encountering is that when I enter my game via Roblox (not studio) the gui is almost completely unresponsive.

I won't post the entire source code, as it's way too long for that, so here's the part where I copy it to the new player:

game.Players.PlayerAdded:connect(function(plr) 
	script.ChatGui:Clone().Parent = plr.PlayerGui  
end)

Here's the link to my place where I'm currently hosting the gui:http://www.roblox.com/games/336727197/Model-Creation-Center

If you can think of anything that I could add to help you help me, please tell me!

Note: I previously said almost completely unresponsive, because I can click one button and it will briefly change color, and because I can still click inside of the textbox used to chat. Other than that nothing else will respond or change.

Tried Solutions:

1. Add a wait()
2. changed script.ChatGui to script:WaitForChild("ChatGui")

why not wait for the character also?

unless u want it to run once

wait()
game.Players.PlayerAdded:connect(function(plr)
 script.ChatGui:Clone().Parent = plr.PlayerGui  
end)

Try this^

You can try replacing this...

script.ChatGui:Clone().Parent = plr.PlayerGui 

to

script:WaitForChild("ChatGui"):Clone().Parent = plr.PlayerGui 

I remember someone helping me with this similar problem.. They told me to add a waitforchild on one part of the script. This might help or wont help. But im just trying my best :)

You should try, going into the in- game and pressing F9 to access the 'console' which helps you identify the LOCATION and the PROBLEM in your script.

Also make sure you put that on a proper type of script paper, e.g: LocalScript,Script,ModuleScript