Ok, built the stand. Used Technora 1/8" rope, rated at 2800#'s for the lines. Used 1 3/8" dowels cause they were cheaper than the 1" dowels. I bought 4 ground stakes (these: http://www.lowes.com/pd_349251-258-G...t=ground+stake
I put it up the first time last night and had a stake failure. The stake just pulled out of the ground. I made some adjustments, lengthened the ropes a bit and lowered the connection point. All held good for a bit, then I had another stake failure. This one was different though. It actually bent the stake against one of the support ribs. you can see the lighter orange stress marks along the plastic.
I think the design is good, just need better stakes that can take the forces. Think I'll go back and try these: http://www.lowes.com/pd_65507-1278-1...ike&facetInfo=