Backup your µSD to a Backup folder on your PC BEFORE upgrading to a new Kernel

Format your µSD with the Panasonic SD Formatter 3.1
Use these options :
FORMAT TYPE - FULL (OverWrite)
FORMAT SIZE ADJUSTMENT - ON

PRIMARY Kernel :
Extract these files from GEi_R4i YSMenu folder and copy to root of your µSD :

Games folder
YSMenu folder
_DS_MENU.DAT
_MENU_.nds
TTMenu.dat


DUAL BOOTING :
Download the latest Kernel from your carts website and extract to root of your µSD.
Extract these files from GEi_R4i YSMenu folder and copy to root of your µSD :

_SYSTEM_ folder
Games folder
YSMenu folder
TTMenu.dat
YSMenu.nds

Boot your carts Kernel, then load YSMenu.nds.