Great information thanks to all. The chapter mode tip was crucial - I was about to call support, and we all know how that was likely to go. I should not assume though.
On the long vs short tracks:
I like shorter tracks so that I can quickly skip through a bunch rather than having to hold the button down. To some degree, this is because on my old Philips Aria player, it would get lost sometimes. I also do books for my wife’s Android phone.
I use an open source program called mp3splt
http://sourceforge.net/projects/mp3splt/ - it has a gui version as well as a command line version.
I put all the original tracks into mp3splt and break them into 5 minute segments. It autonumbers the filenames by appending digits with leading zeroes to the name. I then use mp3tag to copy the filenames to the title tag.
I do use mp3tag to (re)number all the tracks from 1 to n, and it has a check box to auto add leading zeroes as needed. I normally set the album tag to be the name of the book, without numbering disks, so all tracks have the same album. Hopefully that will not be a problem, but it is easy enough to leave it blank too.
