First of all, thank you Krikzz for this update. The EDN8 is the reason I got a Famicom a couple years ago.
My hardware: AV Famicom without any mods, EDN8 Famicom Edition + Kingston SD card. Formated the SD card (FAT32 with 32KB cluster size) and copied the OS folder and after that the roms. I disabled ROM sorting in the menu.
I tried Castlevania III J+Eng up until level 2 and it worked fine, including save states. Mr. Gimmick also works perfectly, same with Doki Doki Panic. The volume control settings are very much appreciated. I turned the volume for FDS games to 72%, the rest is fine at 100%.
Reseting to the menu doesn't work in RC1 for me. It shows "OS init..." and then goes to a black screen. Works fine after a hard reset of the console.
Fixed with a different FAT cluster size.