I mean forensic images for recovery, those ones described in the second post in the following thread:
https://www.mobileread.com/forums/sh...d.php?t=233580
My kindles are B017 22 and 9017 22.
Since people in the thread above report that CM worked after the downgrade it seems that active content works in this firmware (since CM is a kindlet), there seem to be only a question of a problem with the non-Japanese 4GB PW2. Theoretically the problem shouldn't occur, since what should matter is not the hardware but the contents of a partition, but I want to make sure. I probably will try the downgrade even without being sure, but it is more encouraging to know that the attempt won't be for nothing. And it seems that the booklet version is a possible alternative.