I have no idea how you set this up, because whenever I try to change something, cubes and stickman start flying all over the screen, but it’s actually quite simple to have stickman follow a curve.
There are several ways for it, I’ve uploaded a blend file with the simplest, cleanest (imo) method at http://tieleman.m.googlepages.com/hidden
You can keep the parent cube, and either parent it to the curve, and choose path follow, curve deform or path constraint… I’d choose the constraint. or manually (or with select the path first, then the armature, hotkey ctrl+alt+C) add the constraint and fill in the paths name. choose -Y as the forward axis, or stickman will face backwards.
A very basic mistake you make is by using a SCALED! path in object mode to follow along with instead of scaling the curve itself. It may not cause problems, or it could also scale up your offset, and all of a sudden your character is gone, because he’s flown halfway across the virtual globe.
You wouldn’t happen to be the same atom as the one on vimeo would you? the one which made that funky stickman movie?