Ah thank you!
Sorry about all the confusion
The answer was simple, and found in your documents.
*PC Engine CD
It is important that the image file (usually .bin) and the CUE file (.cue) match.
CUE files are just text files containing a description of the CD. If you have files named like:
Akumajou Dracula X.bin
Akumajou Dracula X.cue
then ensure the first line of the CUE file contains:
FILE "Akumajou Dracula X.bin" BINARY
Any of the following are wrong and will not work:extension has incorrect case
FILE "Akumajou Dracula X.BIN" BINARYfile name has incorrect case
FILE "AKUMAJOU DRACULA X.bin" BINARYdoes not match the actual file name
FILE "Akumajou_Dracula_X_-Chi_no_Rinne(NTSC-J)_[KMCD3005].bin" BINARY*