Uncaught Error: Module Font7x11Numeric7Seg not found

Was hacking about with s7clk.app.js
I commented out the date and seconds display code and uploaded as s7clk.app.js
Now when I try and run the app I get an exception.
I reuploaded the original app.js back to s7clk.app.js but still get the same exception.

Where do these fonts live on the watch ?

Also wondering how the 7*6 works in the code.
It looks like you are scaling the x,y to work across bangle 1 and 2 but not sure what is going on here.

  var size = Math.floor(g.getWidth()/(7*6));
  var x = (g.getWidth()/2) - size*6;
  var y = (g.getHeight()/2) - size*7;