In the human rig there was some code with lots of functions related to math and stuff which looked at first glance to be for real time control of a rig. I see now it’s connected with the rig you used for your character… some sort of auto rigging tool right?
You won’t have to program physics or gravity, they are part of the game engine already.
Anyway… My advice would be to spend some time learning about modeling first. I spent about a year on the basics such as UV unwrapping and edge loops before getting involved with the game engine. If you want to jump right in with making a game you can use simple shapes, like a stick man or whatever while you learn about rigging and animation.
The rig you used didn’t have any IK (Inverse Kinematics) which can help to make animation much much easier. Once you learn about those things you can make a walk cycle easily.
Here’s a good tutorial about rigging:
Some rigging tutorials are too complicated to understand, but that one starts from a very basic setup and doesn’t try to introduce too many difficult things. Notice the character he’s using is just a blob man. Nothing special, just right for learning.
Here’s another tutorial on the same subject, but with words and pictures, so it’s easier to follow:
I don’t like video tutorials myself, so I find something where there are step by step pictures and text much more comfortable.
Once you’ve got a working rig you can move on to walk cycles:
Finally check out the tutorials I linked above:
These will show you have to get your walk cycle working well in game, and further how to add things such as shooting a gun, and controlling the camera.
It’s not easy to learn how to make games in Blender, but it’s easier than other programs I’ve tried. If you stick with it and treat it like a series of assignments that have to be completed you’ll be rewarded with all the skills you need.
One final piece of advice is to steer clear of any tools which promise to do all the work for you, such as make human or auto rigging scripts. You won’t learn much useful stuff when using them and the end result is often not very useful for Blender games. For example Make human always makes characters who are too detailed and high poly. Every time you do something yourself, either by following a tutorial or just experimenting with some ideas of your own you’ll be improving your skills.
I started using 3d software in 2003 and I haven’t had anyone to teach me so my progress has been slow. But finally I feel I’m at a stage where I can do most of the things I want without hitting a brick wall. I do still have to ask for advice though and sometimes I’m completely stumped by some of the problems which Blender throws my way.