the Q adjustment will determine if there is a hump at the frquency you have selected or if it rolls off quicker. A value of 0.7 is what a basic Butterworth filter uses-it has no hump and the smoothest roll-off. A higher value will give you a boost at that frequency where a lower value will roll off quicker.
What driver version are you using. I have to try to remember what plugin packs installed, but I think the crossovers I used were included in the newest driver pack. The kxproject webpage is outdated on the drivers. Goto
www.driverheaven.net forum webpage. The newest support is located there.
Newest Drivers linky
UFX plugin linky-this is the one I think had the crossovers and the Timebalance plugins.
ProFX linky-this had some really nice parametric EQ's IIRC