I know I wouldn't want to give up launching without internet, Nintendo systems seem to have really underpowered wifi, and while my other stuff works fine where I usually am for interneting, my DS and 3DS get really spotty results there.
Folks the save encryption issue is much more complex than blanket statements such as upgrading or downgrading will or will not break saves. Roms vs carts. What encryption they use and if the saves were or were not created on emunand all are important.
Read the emunand /save data mega guide at the top of this sub. Or don't and wing it.
Cearp's cia is a permanent solution that messes around with the sensitive bits of the 3DS. I personally wouldn't touch that without an ability to backup/restore nand by hardware.
Besides, I think the link was removed anyway.