I have a old 3ds on firmware 4.4 and just recently the SD card slot got broken or something (maybe dusty. I really don't know) I just want to know if there is any custom firmware out there that I can install on the system given my situation. (Trying not to send the system to fix because I don't want people updating it) On a side note: I have a new 3ds sys 9.0 emu 9.5. Should I link my nintendo account to the system? What are the advantages and disadvantages of doing so?