[jhowell]

You can save the book.kdf file created by the previewer for later use. You need to also save the 'res' directory associated with it, if any. It holds the images and fonts of the book.

You can open the KDF book with the previewer using the control-O command, at least under Windows. You need to navigate to the directory where you saved it and manually enter the name book.kdf in the open dialog. This works even though .kdf isn't shown as a supported format.

To re-open properly the file name must remain book.kdf. This file name seems to be hard coded into the previewer.