Literally three days ago. That's what made me check on an older version.

Seems like 2.68 isn't compatible yet. I downgraded down to 2.67 and it seems to be working fine now.

I'm having enormous trouble getting SMD tools enabled on blender version 2.68. On the SMD tools site it says it works on 2.63+ so I should be good. I've tried installing it manually the way you did, and I've tried installing from file. Both times the check box is gray and I get a massive error message when I try to enable. Any hints on how I might proceed?