As promised, I've updated the main download and you can get the new version here. This contains the Arduino libraries from the last update, the improved label spreadsheet and the new keyboard back panel as shown below:

This is the same as the previous version, just with new labels and the back panel. I also removed a row of holes from the bottom and sides of the perfboard as they were surplus to requirements.

The case back slides up and over the sides of the bezel and the end result is a nice tight fit.