Hello,
and thx for your effort in making/providing this (bit confusing) Tut and Stuff!!!
Got to mention, that Windows 8.1 GDR Releases seem to be removed from Updateservers, so you definitely have to flash those on your own by downloading .ffu from Lumiafirmware.com.
I found out, that you can upgrade to Win10 (buildnumber shown in first post from neoloko) without editing registry, by simply flashing all the Files from his BackUp (dunno if denim is still reqeuired befor doing this, but Bootloader has to be unlocked and Massstorage-mode!). Be aware, that this eventually leads to a change of your Phonedistrubutor (EU or GB etc. to PL), and maybe some diasabled or not function Apps or particular Hardware (3G/4G/LTE/VoLTE/SIM-Lock). Did'nt testet it all yet, and will report in a few days, but for now it works fine and flawless.
HARD RESET AFTER FLASHING BACKUP NEEDED (as Neoloko mentioned allready)!!!
IF SOMETHING WENT WRONG (UNBRICK/BOOTLOPP), SEARCH GOOGLE FOR FLASH/RECOVERY LUMIA THROUG .VPL (according/corrosponding files that belong to your initial .FFU needed to work!!!)
For me it worked fine, received the latest 2018-05 Update for arm based Windows Phones on it. Also some Lumia-apps that came with his BackUp are working.
So in Final it all goes without editing the Registry of the Phone. Dunno if futureupdates are working too without regedit, but i'll think they will not, cause MS outlined the Support of 1020's. So if you want to be up to date untill MS crops the support in end of 2019 for those Lumia's that actually supported, you have to do the trick via regedit every time you want to Update, or use a full 1020-BackUp of someone who is on the latest WPH10 Build! I dont need this atm, cause i had no relevant Data on it, and only want to use it as Camera, for Calls and WhatsApp. So decide by yourself if you wanna goe this way and risc some Hacking of your Phone through bad Peoples arround the World...
Ps. there are some other Tut's outside of XDA for doing the Trick with regedit via InterOp-Tool (installed WP10 needed!), Windows Phone Internals, and some are through Windows Developer Programm/Tool.
#Typing errors are mine
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