Unfortunately, making images fluid isn't ideal and can cause issues in some browsers. Personally, I would strive to make what surrounds the image flow with the image(s) instead.
This hasn't been implemented yet. Half will look like the one discussed here only somewhat longer. Half will have one more column and be longer.
http://westbound.wikia.com/wiki/Thread:2489?useskin=oasis&cb=2132
I don't foresee that being much of an issue. You can always make the table(s) 100%, but IMO, that would be worse than simply centering it.