Follow up: KUAL, MrPI, Python (all from NiLuJe's snapshots) all appear to be working fine on factory fw. LibrarianSync wouldn't install via MrPi +
update*.bin method (package too old?). Had to download
librariansync-master.zip from
GitHub, extract and manually copy
librariansync folder to extensions. After that, everything was working perfectly.
Well, not quite. Couldn't figure why sort order Recent wasn't updating properly but apparently, I just had to fix the date via
;st Y-m-d H:M. The Kindle allows changing the time via settings (which I'd already done) but not the date.
If I'm feeling adventurous tomorrow, might install the screensaver hack. This seems a bit more risky than the others though so will see.
Got my hands on another PW3 running 5.8.11 (not mine, probably was updated). On a lark, I copied the factory fw 5.8.9.0.1 to that. Surprisingly, instead of automatically deleting the file (as the 5.9.x firmwares do), UYK menu item was active. When I connected it to the PC, the
update*.bin file had been renamed to
update-0-uuid.bin which I promptly deleted. That's the extent of what I did. Didn't want to risk bricking that Kindle.
In any case, would be good if we're able to collect more data points for this method. I think it may work for firmware 5.8.11 and below. Just need to figure out what causes the bricking.
Again, my PW3 was purchased from Amazon US just 3 days ago and came with stock 5.8.11 fw. I think I posted the build number in the 5.8.11 downgrade thread. Never registered to Amazon (had it marked as gift) and never connected to wifi. I pretty much downgraded as soon as it came out of the box.
As best I can remember, here are all the steps I did prior to downgrade:
- turn on Kindle
- select Language: English US
- restart (hold down power button) when it asks to set-up wifi
- delete Set-Up Your Kindle
- connect via USB
- copy factory 5.8.9.0.1 to USB root then disconnect
- charge Kindle (USB wall wart)
- took a break, ate some pie (maybe 10-20 minutes?)
- came back to see the tree and after a couple of minutes, Kindle restarted and was running 5.8.9.0.1 (note, it just auto-installed the factory firmware while I was eating, I didn't have to manually select UYK)

again for all the help!