Getting a 404 not found here, plus the link tries to go to 035d.zip.
http://jetbook.net/upgrade/JL04_v035d.zip
I've tried:
035d.zip
035d.exe
035g.zip
035g.exe
Greycap, perhaps you are using the Lite firmware? Presumably the JB firmware is the "official" ADE release.
EDIT: Very interesting. If I follow the link from here:
http://jetbook.net/update.php
It works. But not he link from:
http://jetbook.net/upgrade.php
Even though it appears they are going to the same place (035d link above).