As has been discussed extensively in the Flexile discussion area... on 1.2.x it doesn't do a LOT of what it should.
In another words, until the author fixes it or someone else takes it on it's borked.
A lot of fixes can be found in the discussion area for that style - but it still does some things differently that some CSS won't work with.
I am well aware this is a very old thread, but I figure I would throw out there my code I have for this which also fixes the body padding and border issue.