Shoutbox

I've been at this for an hour and a half or so and have followed the Scripting Documentation to the letter. Looking in the section Working with scripts->Windows for your scripts it isn't working. I checked the debug window and no errors. The code in the script is this:
function OnEvent_Initialize(MessengerStart)
{
var Wnd = MsgPlus.CreateWnd("InterfaceTest.xml", "WndTest");
}
function OnEvent_Uninitialize(MessengerExit)
{
}

And I made the file InterfaceTest.xml (Which is really a .txt file...) with the exact copy/pasted code in it (Its a bit large so I wont post it...). I have also tried making a copy of another XML file, editing what it said, and using it instead. I have no idea what to try now. Any help would be appreaciated.

EDIT: It works, but now I have another question XD. Can someone just give me an example of a working OpenChat command? I have been trying to simply open a chat for a long time...>.>