0 isn't anywhere in the scripting itself. The error occurs when you're trying to msg. Like if you just type 0 and hit 'Enter' like if your trying to just chat like normal. It isn't a major bug, because rarely someone starts a line of text with 0, but it is an error nonetheless.
By the way, Updated. Windows XP Users should be able to use the script now. Please let me know any more errors that occur.