I don't know the technical details, but the impression I got from reading discussions is that the NAOMI issue is due to something with RetroPie specifically and is currently being investigated.

The Virtua Cop 2 issue with freezing upon firing with a lightgun is isolated to the libretro port of current Flycast, and it doesn't seem that the issue is being investigated.

Works now...thanks for all.

@lostless Thanks! I will have to look into that!
It's amazing what you did with your PlayStation theme you've made. I'm a huge fan of it. :)

I am looking for an older lr-flycast core for RPi3 B+ , if anyone has it, please share it. Thanks.

@dankcushions Thanks for the quick response. Kind of sad that it's the effect of video transfer and not an improvement to the game itself. But I'll try that configuration change to see what it does for the game! I appreciate it.

@sirhenrythe5th wow i didnt know that ;D

Reset the core options in /opt/retropie/configs/all/retroarch-core-options.cfg by deleting the lines starting withreicast_.

@mitu I will try that, thank you !!!!

@drdave79 For a minute I thought you were trying to extract a Naomi/Atomiswave rom and ended up with files in that naming scheme. Whoops! Glad you could figure it out.

@derekr resizing to 512x512 seems to have fixed a lot of the issues. Another one that I came across was that the ".PNG" extension of a couple of my files was capitalized. Make sure that your files use the lowercase ".png" extension.

@romhackfanatic Yeah bangai-o stuttering is usually a lack of bios. You just need to download the dc bios, create a dc folder in retropie's bios folder, and then put dc_boot and dc_flash inside it.

@mitu Worked!

Aha! I see it was failing to find the BIOS - I didn't consider that because literally every other game has worked perfectly. dc_boot.bin and dc_flash.bin were both in there, but they were the wrong files. Have now replaced them and everything's peachy. Cheers for the tip :)

@goombah111 I'm using lr-flycast and sonic adventures 2 runs well on it.

@chaoseffect I was using an official BIOS. After switching to the HLE bios, it now loads. Thank you so much!

@donmonii Did you fix the problem? I recently encounter the same problem.

Thanks for this @inolen!

This morning I tried:

-Sega Rally - Ran great
-Kiss Psycho Cirus - Ran around in the first room but seemed to be fine!
-Puzzle Bobble 4 - Playable but with a bit of slow down (it seems so simple too...)
-Super Runabout - Seemed to be full speed but with intermittent stutter.

@g30ff Thanks. The latter was it. Much appreciated!