@mitu I figured that was the case. Thanks for the response!

@barbudreadmon
Thanks, I'll check out some hacks based on that.

@mitu Yep, cheat works in mame2003-plus (and you can make a savestate for each version to save future faffing). The one place I didn't think of looking, cheers :D

Will take a look around, thanks. Just to be clear, I don't have an es_systems.cfg in the directory right now, doing that will cause it to appear so I can modify it? Sorry to clutter the thread, I'm still pretty new to this stuff. I'm running the latest version of RetroPie on a 3b+, if that makes any difference.
Edit
Should have clicked the link before responding, all good now! Thanks for the quick response and help

@tobas Are you using a Raspberry Pi or a PC?

You could also look into the new(ish) run ahead feature. It helps to eliminate input lag and from what I understand works very well on early system emulators. https://retropie.org.uk/forum/topic/17438/new-emulation-method-to-eliminate-input-lag

Seems he is testing with some new features and changes, but first completed the base version of the game. Now, he can experiment and edit on top of that version. Makes completely sense now. But where a shadow is, there is a source of light too. That means, we can hope for a future release. Man, I didn't know how cool the romhack scene is.

I know what you're talking about. That's the MESEN emulator. It's supposed to be cycle accurate which means it's likely too processor intensive to run on the pi. There is a libretro port for it, but it doesnt seem to appear in the retropie selections. Maybe look in the experimental cores.

@capeman Well that's leaps and bounds better than my NES/Atari setup

@freakE thats good. I will leave my last post i just posted as it is because it too can help people.