Move book and learner tune link to centre of bottom row, and add popup text. The parts display is not uncomplicated by the images, and they have explanations - at least some users I've spoken to did not understand what they do.

syntax: glob

*~
*.ps
*.pdf
*.aux
*.log
*.orig

syntax: regexp
build/
graphics/
web/Morris.*/
web/Session.*/
web/Library.*/
Morris-.*
Session-.*