The main concept of this tarp design is to have a tight support rope under the tarp between opposite corners. The tarp needs to be attached to the center support rope but it should not be pulling on the tarp when the center support rope is pulled tight. This is done by tying a 1 foot loops in the rope where the tarp corners will be. The loops are tied through the corner grommets and adjusted for tension. The center support rope should be tied tight at 10 - 12 feet above the ground to give you plenty of head room. The other two hanging corners can then be tied with ropes and pulled out. The corner ropes should be lower than the center rope and tied with little tension.
I also used a oak "stick" 1/2" x 3/4" x 6" with a hole at each end, (diameter of the rope used), to act as a tensioner.
The instant hammock, by the way, is an awesome idea. I have one in my bedroom. If you like it check out my Hammocking instructable, How To Backpack Better With A Hammock. Aslo, feel free to join the group, the more the merrier!
I see you use my favorite pink polyester rope. I have easily used 1,000 feet of that in the past 20 years. It is great because it never stretches like ALL nylon rope does.
I'm having trouble understanding step 5. Can you add pictures or diagrams?
Can you use a larger PVC pipe (1.25 inch) and a regular connector instead of the heavy metal and welding up a connector?