I hav Navifirm+ , i check it and i found a lot of ROMS for Lumia 1020, but i cant install it in my RM-877, i found one of TELCEL (im from Mexico) but when i wants to Install it with NOkia Care Suite 5.0, i hav an error :/ and i try again but with the original ROM (AT&T Yellow) and its correct, my Lumia start to install the original ROM.
How i can install other ROM to my LUMIA??