The problem with the curvature based method is the hard edged lowpoly mesh. You get literally 0 curvature data from that. That was the 1st thing i tried.
It is looking really good, the detail you can get with a normal map is pretty impressive. Myself was introduced to the technique, and got good results for the 1st try.
http://en.wikipedia.org/wiki/Hypocrisy in B4lock! the most reasonable comment on the whole issue in this topic... even though I only read the 1st and the last page.