Penumbra: Overture piece of string problem

[Vidda89]

In the game Penumbra: Overture I am playing the game on my mac. I am having trouble in the game.


The part of the game where the player has to create a fuse from a piece of string I am having trouble accomplishing this.


I can not pick up this piece of string from the box while I am playing the game on my Mac.


What should I do?