Eep, you left a _MACOSX folder in the Zip. Other than that, pretty nice.
EDIT: Looked through the code and your // comments are a bit wrong.
%client.plastic += 10; //Adds 5 plastic to the client
Should be 10
%brick.percent += 10; //Adds 5 to percent, making the brick +5% completed.
Again, should be 10.
Those were just some small things, again it's pretty nice.