What is the guarantee that every .exe is in .net?
It is a free and respectful internet. If you don't know how to write a bot and someone took the time to learn and write something you love, be respectful and appreciative and pay him the money for the licence. It is the least you could do.
I think you might have a better time learning how to write your own bot and you will get skills that will forever help you in the future, rather than learning how to reverse one program that you will outgrow in afew months to years. My 2 cents.