[HIG] Button alignment question

[Jonathan Blandford <jrb redhat com>]

I have a number of dialogs with a vertical row of buttons on the side.
Some of them have stock items next to them.  Should I left-align the
buttons in them at all, or keep them all centered.  I put up a set of
somewhat contrived screenshots at

http://people.redhat.com/jrb/files/higquestion/

Just to give some context, the "Theme Details" button at:

http://bugzilla.gnome.org/showattachment.cgi?attach_id=16822

Gives the dialog that posed it.

Thanks,
-Jonathan