Unable to create threads

I am unable to make my own thread. Even tho I am an administrator...

Admin: Set to YES to all.
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What's the difference between Sibling Node and Child Node? I created a category and then a forum page....
Thanks. I finally understand it...A bit confusing if you asked me..Now, my other question is Brogan. I have FB merged and it worked. How can I get my feed that I post on my forum go to my FB?