Okay so I have successfully downgraded to 4.2.0-9U sysnand. Do I have to install the MSET exploit or can I just use the gateway FW through spider and boot classic mode to install BigBlueMenu(correct me if I'm wrong, also sorry for the off topic questions)
Ninja edit
IMO it's must faster to just use the MSET Exploit to run rxTools. The main issue is installing BigBlugMenu, which you already have an idea on how to install it.
Ninja Edit : I had a brain fart, if you have a flashcard, use the NDS file included to install the MSet exploit. Otherwise you need to use Spider to use set the MSet exploit.