When we made the plan, I didn't realize that the first day of our book sprint is labor day! So there was time for a thorough inventory. What do we have so far? I used the time to go over every chapter and put notes and comments in chapter talk of the particular chapter. If you login to FlossManuals, you'll know what I mean.
In order to get finished, we need to cut back on some things. Put everything in we need and leave out the nice-to-have stuff. This will of course not be deleted, but put into appendices or other files for later use.
One convention we agreed on was to base the manual on Etoys 4.0. I think this should still be the case, and we should add notes for the changes in the new Etoys 4.1 version.