Like the earlier puzzles, the goal of this puzzle is to clear a clash.
Madde's "Backbones Collide" video
Loci's "Backbones Collide" video
Foldit Research's "Backbones Collide" video
The shake tool is still available. Shaking helps the score, but it doesn't clear the clash.
To fix this clash, grab the backbone of the protein at one of the ends, and drag it away from the backbone on the other end.
Technical stuff: this protein looks at lot like the one in the previous puzzle, Shake! Dragging on the ends of one of the two helixes in this puzzle is the key.