i’m on retropie 3 beta and i can confirm it works great. I have 3 games: akumajo, spriggan and wings of thunder. syscard3.pce is in my rom folder and in bios folder.

Take care to not break the cue file when you edit it, like adding a space or any character.

Perhaps something related to the Character_encoding of the cue file. If it’s in UTF8 for example, maybe you have to open and save it in UTF8 in you text editor…