Did you notice the characters coming apart at the seams, like slinky toys? I've been curious about this problem. I thought it might be a CPU bug but I don't think Ville encountered it with his Direct3D version back in the day (still using the same CPU core here).
Direct3D handles Step 1.0 a lot better than OpenGL. Step 1.0's coordinate format differs from all other Model 3 revisions. I use a trick to get it to look acceptable, otherwise there would be serious Z-buffer problems. It seems weird to me that most of the scenes look solid but the characters tend to develop seams and gaps when moving.
It'll probably solve itself at some point down the road. TBH, I'm more interested in the problems the Step 2.1 games are experiencing at the moment. I know what's causing some of them but was too lazy to fix it for this release.