Last night I removed the bottom poles, slid them into the sleeves, and reattached them to the rest of the frame, and it became harder and harder to use the half-width nuts that came with the kit.
Based on the picture, I thought the poles were supposed to go further than they are supposed to.
The corner feet curve around 90°, so you really cannot secure the poles lower. I tried anyway, or started to, but I realized that you needed to tighten the cover first, and before that you need to properly attach the ends.
You tighten the drawstrings around the frame and tighten the cargo strap.
I need to take one of the nuts to Cal Ranch to buy a full-sized replacement and secure the back side. The cover is pretty tight. It was too late to run the sprinklers, so I threw about a gallon on it, and none of it really collected, so hopefully a heavy rain will not result in a 6-pack of alien udders!
I will run the sprinkler in the morning and if everything checks out I will replace those nuts, drive the ground anchors, and secure them to the corners with cables.