Shoutbox

Check if the RegExp is right...
In the OnEvent_ChatWndSendMessage function, the first line should be:
if (/^\/TZSetGMT\s(?:(.+)\s)?((?:\+|-)?\d+(?:(?:\.|,)\d+)?$)/i.test(Message)) {

The way you describe it, it looks like you don't have the latest update :S

-edit- Much more readable when smilies are disabled :P