I can't believe I'm defending Kobo (
) and how they have handled this upgrade but on the 6th Oct MDK posted a warning indicating that going forwared there were going to be incompatibilities between various firmwares and some devices.
The warning is repeated on the thread where the firmwares are posted.
If people choose to ignore the warning they have to accept that they may end up with a brick.
In any case the first poster to be told that he had "broke" his Glo was soon given a solution which fixed it.