I'm trying to make some character poses from reading c2552's http://www.fallout3nexus.com/articles/article.php?id=244 article, but I've run into a problem. I've created a sitting pose but if I sit down and activate it, the character slides backwards to complete the pose: http://img.photobucket.com/albums/v483/Tubal/F3/ScreenShot88.jpg
Obviously he's supposed to be leaning back in the chair, not through. Simply moving the pose in blender doesn't make any difference.

Any ideas?

If you're not sitting in a chair (just standing around somewhere) and activate the pose, does he still slide back?

Yes. Fallout interpolates the movement to the static pose I've made, but it's not oriented around the point *I* want it to use.
http://img.photobucket.com/albums/v483/Tubal/F3/ScreenShot97.jpg

I'd like the centre of the pose to be somewhere around the his waist, so he ends up in the correct position when sitting.

Here we go: There's a bone called just "Bip01", where all the others are called "Bip01 Thigh.R" or whatever. Move it and everything else moves. However, move everything else, but not it, and the pose centre shifts.
I'm assuming it is the centre.

Anim.kf is most likely Missing Controllers/Incorrect Data on them OR... you did not pose match and furniture expects things to be where they are suppost to be ! thus you get incorrect positions -> this is less of an issue if you imported an Beth Anim then if you created from scaratch though so its most likely the first problem.

hard to say without the anim in question and exactly which animation that it was based off of (which anim you imported to get the default before you moved bones positions).

Moving the Bip01 bone was enough to get it where I wanted it: http://img.photobucket.com/albums/v483/Tubal/F3/ScreenShot100.jpg.