Go to Hinterberg.com. They've got instruction sheets for everything there, and you can email them with your questions. They're very helpful. Yep, it just sits on the wood shelf. With as much as that machine weighs, trust me, it's not going anywhere! As long as you have it centered on the shelf, it's correctly centered. You want it a bit larger than the shelf so the machine can quilt as far as it can without the shelf stopping it. It sure looks to me like you've got it set up correctly! Have a ball with it!