Some FX are post-fader, meaning you wouldn't hear them because the headphones preview the channel pre-fader. You would be able to hear it on the master because it's already been applied at that point. There is no ability to change it, sorry.
As for the CFX release, that simply allows you to apply a release-FX and have it also disable any color FX you were running at that time. Some DJs want to keep things like a filter engaged, so they turn it off, whereas others want to clear ALL FX and CFX when hitting a release FX, so they enable it.