Hmm, yeah, ill have to have a think about that one, there are some additional (non css) properties in the haxeui css engine, so you could affect some things, but as you say, its working on a haxeui style, so that is a limitation there.
Out of interest, do you have example (regardless how useless) of something you hand in mind that shows what type of layout stuff you would like to effect based on a state? Just curious really to see if haxeui could already do it.
Cheers,
Ian