Hi ZephaHD
The first problem I see is that you would have to create your own Zombie characters as they would have to be custom and character creation is one of the most difficult things to learn.
Secondly You would have to lua script ..There would be no way around that to get the results you require ..
Personally I think trying to create a 50 million budgeted game on £14:99 GameGuru is a little ambitious
We had some brilliant Military Zombies in Fps Creator but they haven't made it over to GameGuru yet ..
The only person ever to get all his work done by "Friday" was Robinson Crusoe..