How I can make a simple follow AI in Unity 5?

Hi. In Unity 4.X I used the basic follow AI from this thread:

But, In Unity 5, doesn’t work correctly. How I can make a simple follow AI in Unity 5?

Thanks.

There is a simple one on here: 1
It is pretty good and I myself use it but in my game when the zombie can’t “see” the player is just stays in place.

I have modified it so when the zombie can’t see the player it just wanders.