Though, yesterday I spent trying to figure out the process, and I have to say it is fairly straight forward. Though it open a lot of opportunities for small mistakes that can have drastic consequences when animating.
After creating 1 arm for about 4 times, I found the solution in a tutorial by Peter Anderson, a Senior Artist with Turbine/Warner Brothers games, which can be found on here.
This type of rig is ideal if you have a character doing different types of motion, for instance IK rigs are better for motions like grabbing, holding, leaning on objects. While FK rigs are better for walks and runs.
In my animation both types of motion will happen, so it is a perfect choice to animate with.
Here is the character body rigged and tested:
FK Arm Rig
IK Arm Rig
These time used doing research and tutorials, to solve the problems can be frustrated, but it will help later.