Nikki uses lots of rope
Here's a description of the contestant's attempt. Someone's probably working on collecting some images to illustrate it.
Nikki goes to the shed to search for ideas, wondering if she can do something with rope and a heavy object. Not much is shown of her actual building process - just that it involves very long pieces of rope. Nikki’s device is started when David cuts the rope tied to the balloons. Nikki makes this more difficult for David by constantly pulling on the rope. However, when David finally cuts the rope, enough rope is left tied to the balloons that it keeps them weighted to the ground. Nikki earns joint last place.
(Written by Jenny R and proofread by Karl Craven)