@mitu
Ah thank you!
Sorry about all the confusion

The answer was simple, and found in your documents.
https://retropie.org.uk/docs/PC-Engine/

*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" BINARY

file name has incorrect case

FILE "AKUMAJOU DRACULA X.bin" BINARY

does not match the actual file name

FILE "Akumajou_Dracula_X_-Chi_no_Rinne(NTSC-J)_[KMCD3005].bin" BINARY*

@Dezmancer See http://retropie.org.uk/forum/topic/2/forum-rules

We cant support 3rd party images. Ask the images author for help.

@Darksavior any news on a retroarch update btw?

Update:

I found these instructions and tested them:

link text

What I did for USB memory stick was to input these settings to be used (settings for regular HDD might be different):

sudo hdparm -B 255 /dev/sda sudo hdparm -S 0 /dev/sda

I first tested them for 30 mins in Driver 2 and then for about 20 mins in Gran Turismo 2 and then again with Driver 2 for 5 minutes. With the Driver 2, I didn't encounter a single freeze in 30 mins. Then I went for the GT2. There I withnessed 3-4 freezes overall. Then I went back to the Driver 2, because I started to think, that maybe heat or something triggers the freezing issue. But on the second tryout with Driver 2, no freezes at all.

So now I'm wondering, that could it be about the emulator software or does the game have differences in data loading methods. Needs to be further investigated and someone else could try with that guide I linked.

Update: I now discovered, that there is audio cuts during the GT2 Arcade Disc's demo, that starts rolling after a while when sitting on the main menu. Maybe the issue could be related to that as well, sync problems you know.

@Jiryn Yeah. If your computer is on the same network as your Pi (and the Pi is running) you can access it via your web browser of choice. I've had it activated for so long I'd forgotten how to make it work, thankfully @ETAPRIME has that covered:

Once active, you can drag-and-drop your BIOS files via the web page. If they're not what RetroPie is looking for it'll tell you then you can seek another source. Saves the time and hassle of repeatedly booting up your Pi to see if you've fixed the problem.