Please go to your preferences page and make sure your "See Mature Topics" setting is set. Setting it to "Yes" means you see the Mature Topics forum (contains political and religious debates). Setting it to "No" means you do not see those threads.
Once you're a lurker it takes 1 post to regain your old status again. You have to wait though till the forum recalculates the usergroups. It does that every hour so you'll have to wait upto one hour. You become a lurker if you haven't posted in IIRC 2 weeks.