I have an over 15 years hands on experience in this field of programming, and graduated from a well respected UK university.
certain aspects about the project are quite vague however, when you said edit exe, are you referring to reverse engineering? if that's the case I assume you don't have the source code?
in this kind of projects nothing cannot be done, but everything has its price and time-frame, so please the more clarification you provide the better
i would precise about quoting you
Good luck with your business and I hope i will be the winner for this bid and I am pretty sure you won't be disappointed