A general observation: Mathematica has been around for many years, and there's quite a lot of code on the internet that was written for older versions. Compatibility is good, on the whole, but it can be frustrating if you're new to Mathematica and find it hard to get code from older versions to work.
About the Game of Life: it's worth noting that you'll find this already inside Mathematica, in various places. Search the Help for more. I quite like this version:
g = Binarize[RandomImage[1, {500, 500}]];
Dynamic[g = MorphologicalTransform[g, {"Life"}]]
