[quote=108057]As per usual you were completely right Mr. Floob.
Pressing Select (Coin) + X (Top button) brought up the RetroArch Menu, under Quick Menu in the Core Settings, there was the option I was looking for!
Found a whole lot of other interesting stuff in there as well!
Thanx again!
[/quote]
Is that working for you? I tried switching to aes and it crashes back the ES for me.
edit: Figured it out. My copy of neogeo.zip needed aes-bios.bin to be added to it.