Most games that do have advanced following AI, are games that have programmers who've learned in school how to do AI. Doing AI will most likely involve heavy programming.
I'm sure there will be problems you cannot get the AI a fix for, so your best bet is to make sure the player cannot do something you cannot let your AI do something helpful with.
A few basics that you would need:
pathfinding (find the best route from point A to point B), closest point (find the closest accessable point near where you want to be) and AI Action points (create interation points for the AI. When they get to one, that point will tell them how to act. Example: If enemy is still at location c, Stop here and get cover)