It has been a while i've done this but as far as I remember the main purpose of this procedure is for extracting the OTP file for your machine. This file is very important and unique for your console, the only way to do this is by going back to fw 2.1 later. And also you might not be able to boot that firmware based off your machine. But, as he explains in the guide its normal.
Thereby i highly suggest follow every step of the guide and do not skip anything. Sometimes you will even question yourself "why do i have to format and re-flash sysnand and emunand for the 100th time?" But, this is the only way to ensure 100% safe arm9lh installation. And yeah btw go for Aureinand aka Luma3ds at the end.
As i said before have patience as someone has yet to release a video tutorial based on this. Eventually you will also flex your 3ds muscle with the Arm9lh boys.
Thereby i highly suggest follow every step of the guide and do not skip anything. Sometimes you will even question yourself "why do i have to format and re-flash sysnand and emunand for the 100th time?" But, this is the only way to ensure 100% safe arm9lh installation. And yeah btw go for Aureinand aka Luma3ds at the end.
As i said before have patience as someone has yet to release a video tutorial based on this. Eventually you will also flex your 3ds muscle with the Arm9lh boys.