Collision will only function during a dynamic movement process, and actually has absolutely nothing to do with styling. I do not, at this time, have much more than basic notes about this scrawled in my terrible handwriting on a few index cards, but this is done using the falloff slider on the hair stying tool. Note as well that hair dynamics are not meant to be used in the styling process -- they are meant strictly to be used with the various animation modifiers (wind force) and will actually "wreck" any style (much like happened to me today when I went to the store...) Although this doesn't help you now, target date for my series on using the Hair room's tools is Septmeber 21st, immediately following my series on using the cloth room. Both will be in the Poser 5 Exlporation Forum at RuntimeDNA, where the Material Room nodes are currently being investigated (the pause while I move notwithstanding).

thou and I, my friend, can, in the most flunkey world, make, each of us, one non-flunkey, one hero, if we like: that will be two heroes to begin with. (Carlyle)