Thanks for creating this, I really appreciate it. Out of curiosity, what is the general structure of the format?
For a bit of background, the BrailleNote was a specialized PDA for the blind that ran Windows CE. The device includes installers for various versions of the user guide among other things, and I thought it would be nice if 7-zip could extract files from these installers. I suspect the data is compressed as a zip file with a specialized header, however I am not entirely sure as my reverse engineering knowledge is limited. I attached an archive of some of these installers for possible investigation...