You might (if you haven't already) want to look at the info on uploading photos here:
http://www.quiltingboard.com/qb-help-center-f27/
Voice of experience (about to post my sad tale) - don't unscrew before you're sure what you're doing! The tension has a spring, so the last time I took one apart, I put a small plastic bag around it while I unfastened it, so I could catch anything that went flying!