setting up a skeleton for a humanoid - Bone IK Chain?

As the topic says, I'm wondering, am I supposed to use the "Bone IK Chain" function?

And how can I mirror it laterally? Example: make just one side of it (arm and leg along with the torso and head), and simply duplicate ONLY the arm and leg part on the other side of the humanoid...

Wc3 Art tools doesn't support Bone IK Chains (it says so somewhere in art tools) so on i highlly i recommend you as samples show you, use boxes as helpers to animate like in art tools samples, it is easier and will save you a long work because animating with bones ik chains and dummies and shit, is a more difficult task expt if you are using Biped ofcourse.

to mirror, you clone, then use edit i think and do mirror (or flip, dont remmeber which one)

biped is for pussys