Simon,
I was successful in adjusting my firmware thanks to your tutorial. All is working great again and im not stuck WebOS 2.0
Thank you so so much!
Dave
I reverted my FW back from 05.00.20 to the latest stable on the website, 04.45.25 in my case, recently.
Whether it is difficult or not depends. I used https://github.com/openlgtv/nsu_emu+ https://github.com/chokepoint/pytinydns and it was quite ok. If you're on Windows you may have luck with the "LgDTVUpDater" which claims to be a one stop solution (untested by me, the manual seemed rather complicated).
HTH