You might find someone here with an answer, but you'd have more luck asking on a forum where the people know what that script is and does. The chances that someone here (on a mIRC forum) know about some specific bot for DotA is rather low. That being said, if you know enough about programming, you can program your own VB or other language bot to understand any scripting or programming language for the most part -- some things may be hard or impossible to duplicate exactly depending on the languages involved. If the original bot's script/programming is in VB, then it should mostly be a simple matter. If it's another language, then you'd have to convert it or write code to interpret the language. That's far from simple, but can be done.
